1. Structure of the minimum set of equipment for prototypes of multiservice system MITRIS-MEDIA code ААБШ.464423.120.

The set of equipment of multiservice system MITRIS-MEDIA code ААБШ.464423.120 contains the following basic elements:

1. The station MITRIS-MEDIA (BH) or MITRIS-MEDIA (BL) ААБШ.464423.121 radio-frequency Unit having two options of execution depending on those, in even or odd sector it has to be established. At the first stage it is possible to be limited to one sector and one option of execution – MITRIS-MEDIA (BL).
2. The subscriber station MITRIS-MEDIA (AH) or MITRIS-MEDIA (AL) ААБШ.464423.122. Execution options also depend on that, in even or odd sector this subscriber station will work. At this stage it is possible to be limited to option of execution MITRIS-MEDIA (AL). For subscriber station work research as a part of a data transmission network it is necessary to make 10 samples of subscriber stations of this type.

2. Basic principles of the system construction.

At system development the technical solutions protected by Ukrainian Patents No. 54643 and No. 54644 were used.
The system of MITRIS-MEDIA (B) represents the radio-frequency Unit of MITRIS-MEDIA system Base station intended for transfer and reception of downstream and upstream data in a station service zone which has a circle form with a radius up to 2 Km. In this zone the MITRIS-MEDIA (A) subscriber stations, which can receive downstream signals and transmit upstream signals, can be located.
The radio-frequency Unit of the MITRIS-MEDIA (B) Central station (CS) represents system from 4 or 8 pairs of sector antennas with vertical and horizontal polarization which are intended for downstream and upstream signals transfer and reception. Subscriber stations like MITRIS-MEDIA (A), belonging to one sector, in the return channel can work at several frequencies appropriated to this sector (FDMA mode), and also in a mode of time division (TDMA) or code division (CDMA) multiple access. In the downstream channel the mode of time multiplexing (TDM) is used. In the next sectors for direct channels different frequencies also are used. In opposite sectors it is possible to use identical frequencies. Thus, for formation of the frequencies plan for all sectors it is enough to have only two frequencies sets for the downstream and upstream channels. Pair frequencies strips of reception and the transfers intended respectively for even and odd sectors are shown in Figure 1. This system can serve only those subscribers for which in strict sense of the word conditions of “direct visibility” between CS and any of subscriber stations are satisfied.
The absence of reflected signals when subscriber stations receive signals in the “line of sight” mode of the Central station, also a high degree of directivity of parabolic-dish antenna of subscriber stations allow you to use spectrally-efficient modulation methods up to 256QAM for data transmission via the direct channel. A large throughput of DOCSIS 3.0 modems allows you to transmit both information signals and digital TV signals in a single digital stream.

3. Frequency plans.

The system works in two frequencies bands:
12.75 – 13.25 GHz – downstream signaling (the frequency plan is shown in Figure 1 above)
10.15 – 10.65 GHz – transfer of the upstream channels (the frequency plan is shown in Figure 1 below).
Each of these frequencies bands is divided into two strips 150 MHz wide, the protection interval between them is equal 200 MHz. For creation of prototypes it is offered to use for transfer only a strip of 12.75 – 12.9 GHz, and for reception – 10.15 – 10.3 GHz.
Division into two strips is caused by need of frequency division by transfer of the upstream channels in the next sectors therefore the bottom range is intended for transfer in odd sectors, and top – in even. Total quantity of sectors always is the even number.

4. Radio-frequency Unit of the Central station MITRIS-MEDIA (B).

In Figure 1 the block diagram of one sector of the MITRIS-MEDIA (B) Central station Radio-frequency Unit is shown.

Signals of downstream channels are transmitted in a strip of 150 MHz by means of the sector antenna with a beamwidth 90 degree and vertical polarization. Reception of upstream channels arriving from subscribers which take place within this sector is carried out by means of other similar antenna but with horizontal polarization. From reception side the bandpass filter with a bandwidth of 10.15-10.3 GHz is installed.

Signals of upstream channels are generated by linear DOCSIS 3.0 cards at an intermediate frequency in the range of 700-850 MHz. After that they will be converted in BUC to radio frequency signals in the range of 12.75-12.9 GHz, amplified on power and by means of the transmitting antenna are radiated in sector in the form of a beam of 90 deg. wide.

The signals of upstream channels that arriving from the MITRIS-MEDIA (A) subscriber stations are received by other sector antenna, pass through the filter with a band of 10.15-10.3 GHz, and reach the LNB. After that the signal of intermediate frequency with a band of 1300-1450 MHz reaches the converter block in which it will be converted to frequencies in a band of 14-65 MHz (which can be received by CMTS).

Figure1. Block diagram of central station radio-frequency unit one sector

5. Subscriber station MITRIS-MEDIA (A).

Subscriber station MITRIS-MEDIA (A) (see. Figure 2) consists of three main parts:

– integrated from an antenna transmit-receive microwave head (iLNB) of external execution;
– the transceiver – the internal block;
– subscriber modem (CPE) of the DOCSIS standard.

The receiving part of a transmit-receive microwave head serves for downstream signals reception in a band of 12.75-12.9 GHz or 13.1-13.25 GHz and their convertions down on frequency in the range of the intermediate frequencies of 1.8-1.95 GHz; and transmitting part – for upconvertion on the frequency of the signal which is settling down in a band of the intermediate frequencies of 650-800 MHz in bands of the frequencies of 10.15-10.3 GHz or 10.5-10.65 GHz (which it is used for transfer on air of the upstream channels). For this purpose the microwave head (iLNB) has two options of execution depending on local oscillator frequency. For the purpose of the maximum decrease in weight, dimensions, and the cost of a transmit-receive microwave head in its structure the common local oscillator for receive and transmit parts with a frequency of 10.95 GHz or 11.3 GHz is used. At this development stage creation of 10 prototypes with a local oscillator frequency 10.95 GHz is supposed.
The transmit-receive microwave head connects to the block of converters (transceiver) by means of two coaxial cables with the small losses intended for the radio-frequency signals transfer and the third cable on which signals of iLNB power amplifier switching off in transfer pauses are transmitted. Converted in iLNB signal arrives on the transceiver block which has internal execution. The signal passes the frequency converter in which it will be converted to a signal with a frequency suitable for reception by the subscriber modem (CPE). The transceiver connects to CPE by means of the duplexer dividing signals of downstream and upstream channels.
The signal of the return channel on IF 14-42 MHz from CPE through a duplexer arrives on the first upconverter by means of which it will be upconverted on frequency to the fixed frequency 1700 +/-14 MHz on which are filtered by two SAW BPFs which are divided by the amplifier. Further this signal will be converted down to one of frequencies in a band of 650-800 MHz and reaches transmitting part of the transmit-receive microwave head. In the transmitting part of a microwave head this signal will convert to one of frequencies in a band of upstream channel transfer 10.15-10.3 GHz or 10.5-10.65 GHz and amplify on power.
Feature of subscriber station architecture is that because of top in relation to an output signal of transmitting part of iLNB a local oscillator arrangement there is an inversion of a transmitting signal spectra. In order that iLNB radiated not inverted signal (the DOCSIS standard doesn’t allow spectra inversion), it is necessary that in the converter local oscillator frequency was chosen so that inversion of a spectra happened one more time. This inversion is made by the second converter of the transceiver transmitting part.
The iLNB antenna has two options of execution:
1. In the form of the two-reflector antenna (Cassegrain);
2. In the form of the horn antenna.
The antenna having a main reflector with a diameter of 60 cm is intended for those subscriber stations which are placed at long distances from CS and horn antennas are used at a placement of subscriber stations at small distances from CS. The supply voltage on iLNB moves by the radio-frequency cable connecting the transceiver with reception part of iLNB; and a signal of the reference oscillator moves by the radio-frequency cable connecting the transceiver with transmitting part of iLNB. In one more coaxial cable the signal of transmitter switching off in pauses between slots transfer. In pauses there is a shutdown of power supply of the power amplifier.

Figure 2. Block diagram of the subscriber station MITRIS-MEDIA (A)

Table 1. Key parameters of transceiver microwave head

Table 2. Transceiver of MITRIS-MEDIA (A) Subscriber station

The transceiver microwave head (iLNB) has the design assuming its outdoor work in severe climatic conditions. The transceiver is installed indoors near the cable DOCSIS modem and connects to it two cables.

Group and single-channel transmitters.

In modern digital TV broadcasting systems a transmitting over 100 TV programs is supposed. Most often used broadcast standards are DVB-T, DVB-C and DVB-S/S2.

For multi-channel signals transmitting group transmitters which will convert generated on IF multi-channel digital signal to a radio frequency group signal and gain it on power for transmitting on-air through single omni-directional antenna or the sector antenna if radiation is made in a zone limited to some sector can be used.

Much more attractive from the view point of a group signal formation convenience the method of its formation on intermediate frequency with the subsequent group spectrum conversion to a working radio frequencies range is represented.

The method alternative to the given, is single-channel transmitters application, each of which will convert and gain generated on IF the separate channel signal. The signals received from N single-channel transmitters multiplexing on a radio frequency are carried out by means of the special multiplexer consisting from N channel BPF (bandpass filters) and the same number ferrite circulators (Fig. 1).

Let’s notice that both methods assume channels frequency multiplexing at physical level (PHY).

Fig.1 Radio frequency multiplexor

Let’s consider the presented multiplexing methods merits and demerits from the view point of broadcasting complexes complexity and cost. For this purpose at first we will analyse the system consisting of the group transmitter and the omni-directional antenna.

Such structure unconditional advantage is its simplicity. It is clear that to generate a group signal on intermediate frequency much easier. However to realise such system it is possible no means always.

As it has already been told, the digital broadcasting can be carried out according to standards DVB-S/S2, DVB-T and DVB-C. In standard DVB-S (S2) systems each of channels represents carrier, modulated on method QPSK (8PSK), i. e. modulation methods with a constant envelope are used. As it is known, the modulation mode with a constant envelope is the most favourable from the view point of system power as for signal with modulation QPSK receiving it is enough to concern a signal / (noise + intermodulation) – SNIR at level 10-12 dB, and for 8PSK – SNIR = 19 dB.

At signalling of standard DVB-C modulation QAM64 (SNIR = 25 dB) more often is used. It is not less than on 13 dB above, than at QPSK.

At standard DVB-T (a modulation method COFDM) signalling on the foreground there is a factor showing the peak to average power rate of one transmitting signal throughout symbol – PAPR, average which value is equal 10 dB. It means that for not distorted symbol COFDM transfer the transmitter should have a power stock on 10 dB concerning a compression on 1 dB power (P1dB). Thus, standards DVB-C and DVB-T transmitter efficiency is approximately equal.

If to consider that the standard DVB-S/S2 transmitter can normally work at power level only on

3 dB low P1dB it is possible to draw a conclusion that for the same transmitter output 1 dB compression point power (P1dB) receiving for standard DVB-C or DVB-T transmitters power should be on 7 dB above, than standard DVB-S transmitters P1dB. We will assume for reasonings cleanliness that antennas of all three systems have identical gain factors. Then and EIRP (equivalent isotropic radiated power) which represent the transmitter output power in dBW and antenna gain factor in dB sum, will differ on the same 7dB.

Thus, the general prize in a radio line power at the expense of lower SNIR (on 13 dB) and more (on 7 dB) EIRP will make for DVB-S 13 + 7 = 20 дБ.

The truth in case the standard DVB-S transmitter is used as group it should possess the raised amplitude characteristic linearity level at which intermodulation products level will not exceed some set level (by transfer over 10 channels it is – 40 dBc). For such linearity achievement it is necessary that transmitter output power was approximately on 10 dB more low P1dB. Nevertheless, the prize and in this case will make 13 dB.

It is necessary to notice that group transmitter power calculation is made in the beginning concerning one channel, but taking into account requirements on the linearity, corresponding to a group signal transfer requirements. It would seem, for transmitter integrated power (PTOT) calculation, necessary for N channels gaining it is enough to increase the power defined for one channel (PCH) by channels quantity N, i. e. PTOT = PCH x N. In practice because a considerable quantity of not only 3rd but also higher orders intermodulation products occurrence which are the adjacent channels interaction consequence – intermodulation with the adjacent channels (ICI), the transmitter operating mode should be chosen even more linear that will lead to that P1dB, it will be essential to exceed PTOT.

The increase in a service zone radius demands with other things being equal to transmitter output power increase. At increase transmitter P1dB its cost increases much faster than power increases. Therefore for some output power value the group transmitter cost will be made even to cost N single-channel transmitters with output power PCH. At the further increase the group transmitter P1dB the single-channel transmitters application becomes more rational.

One more standard DVB-T feature is a single frequency television broadcast network application (Single Frequency Network – SFN) possibility in which the adjacent transmitters can conduct simultaneously broadcasting on carrier frequency synchronously transmitting the same multiplex, and receiving areas of their signals are blocked. In overlapping zones thanks to application COFDM presence of signals from two transmitters not only does not worsen reception quality, but on the contrary, presumes to improve reception at the expense of two signals powers addition. Use of a single frequency network allows to capture land TV-broadcasting the big territory, having distributed on it demanded quantity concerning low-power transmitters.

From the resulted reasons it is possible to draw such conclusions:

1. Group transmitters are expedient for using in those systems in which modulation types with a constant envelope (standards DVB-S/S2) are used.
2. At transfer by standards DVB-C and DVB-T group transmitter signals the channels quantity can be no more than 2-3. At much channels quantity them to use it is inexpedient because of their progressive increase P1dB.
3. For the big territory coverage by rather low-power transmitters it is necessary to construction SFN resort.

The Method of on-air frequency multiplexing.

At broadcasting complexes designing very often there is a problem of a great number (from above 100) TV channels transfer in the limited frequencies band. Thus a service zone radius can make 50 Km and more. In one channel the multiplex from digital TV programs, including no more than 10 TV programs is usually transferred. For transfer 100 TV programs are necessary for using not less than 10 radio-frequency channels (radio trunks).

Single-channel transmitter application necessity as the group transmitter will be excessively difficult and expensive unequivocally follows from a task in view.

At a following design stage it is required to solve radio channels multiplexing way choice problem for the purpose on-air radiation of all signals obtained from single-channel transmitters. The multiplexer shown in Figure 1, is suitable for this purpose, but is expensive, and its manufacturing and adjustment are rather labour-consuming.

Besides, it brings big dissipative losses and demands introduction in structure of each channel path delay non-linearity compensator (equalizer) that is caused by presence at a path of the narrow-band filters which are the main phase distortions source. Therefore in declared system application of a frequency multiplexing method directly on air is offered.

On-air frequency multiplexing is a power addition in space method of the different frequency signals radiated by separate omni-directional antennas, each of which radiates a signal only one channel transmitter. All antennas are omnidirectional. Mutual antennas influence against each other which can deform their orientation diagram should be shown to a minimum.

Further the first variant of a similar complex realisation on an example of the MMDS Transmitting Complex in a range 5.705 – 5.825 GHz will be presented.

The short description

Initial data: The transmitting complex of MMDS in a range 5.705 – 5.825 GHz is intended for multi-programme (more than 100 TV programs) TV broadcasting within a service zone in radius more than 50 Km. The broadcasting should be conducted in standard DVB-T or DVB-C. Carrier quantity is 12. Thus, on one carrier it should be transmitted in one 10 TV programs multiplex of usual broadcasting quality SD. It is possible only at application of the digital compression MPEG-4 AVC (H.264) standard. A band occupied with one radio channel is up to 8 MHz. As all radio frequencies band is equal 120 MHz, the step of a frequencies grid between the next channels can be 10 MHz.

Calculation of system power:  For the given design two rigid restrictions are characteristic:

• On a frequencies band (120 MHz);
• On an system energy potential which is limited, on the one hand, by use enough energy-wise ineffective modulations COFDM (PAPR = 10 дБ), and, on the other hand, necessity of a service zone covering having the considerable sizes (with radius more than 50 Km).

The transmitting complex will be established in a town on which suburbs one-storey building prevails. Therefore power calculation we will conduct for the propagation conditions close to line-of-sight (the easiest Ricean mode).

Let’s take advantage of the formula recommended by the International Telecommunication Union (ITU).

It has such appearance:

10N*log d = PT (dBm) + GT (dB) + GR (dB) – 32.44 – PR (dBm) – 20 log f (MHz).

In the given formula:

PT = a transmitter output power (dBm);

GT = gain factor of the transmit antenna (dB);

GR = gain factor of the receive antenna (dB):

f = average working frequency of a radio channel (MHz).

Let’s accept as initial following sizes:

• PT = 30 dBm;
• GT = 13 dB;
• GR = 30 dB;
• f = 5765 MHz.

At spectral density of thermal noise in the antenna – 174 dBm/Hz we will define a signal power on a receiver input in a band 8 MHz PR, necessary for confident reception, as the sum of the a necessary signal/noise rate (SNR = 25 dB) and a noise power on an input which consist of antenna noise in the channel band and the receiver noise factor led to an input (equal 3 dB):

PR = – 174дБм/Гц + 10 lg (8* 10 6 Гц) + 3 дБ + SNR = -174 + 69 + 3 + 25 = -77 дБм.

Factor N which is called “loss exponent” and characterises propagation conditions on a link we will choose from Table 1.

Using cited earlier given we will settle an invoice in the beginning for a mode line-of-sight in the pure state (N = 2).

20 log d = 30 +13 + 30 – 32.44 + 77 – 75.21 = 42.75.

From here d = 137 Km.

For the most easy mode in the conditions of a town (N = 2.7) we will give d = 38 Km.

Conclusion: for conditions line-of-sight power of 1W will be sufficient for a covering of a zone in 50 Km radius with some stock.

Let’s be guided by power 30 dBm for one radio channel in width of 8 MHz.

We can consider two possible schemes of construction of the Transmitting Complex:

1. With system application from four sector antennas, on each of which the individual transmitter is established. The transmitter should gain 12 – frequency group signal with total linear power 12 W (+41dBm). Because of appreciable intermodulation between the adjacent channels occurrence danger the stock on power of such transmitter should be much more than on 11 дБ (P1dB will be more than 300W, i. e. It is more 55 dBm).
2. With application for each channel of the separate transmitter and the slot-hole omnidirectional antenna. Thus P1dB = 10 W (40 dBm).

The first variant should be rejected because of is inadmissible high value P1dB.

The second variant demands designing of antenna system construction and the new approach to the single-channel transmitter parameters estimation – Block Upconverter (BUC).

The antenna system can represent a two-storey construction. On each of floors six antennas in corners of a hexagon with the party 1м are established.

Each of six antennas not only radiates a transmitter signal but also receives the signals radiated by a number of located antennas. To estimate level of received signals it is reversible to the diagram in Fig. 2. The given diagram shows losses in space in a near zone around antennas which are resulted for two modes: a mode of line-of-sight (LOS) and a mode non line-of-sight (NLOS). The minimum losses in space (for mode LOS) on distance 1м make nearby 40 dB. To calculate, what level will be received on an antenna flange (directly on BUC output), it is necessary to subtract from this size gain factors of two antennas (transmit and receive) in dB, i.e. 13 + 13 = 26 dB. Thus, the signal received by the antenna will be on 40 – 26 = 14 dB less, than a signal radiated by it. The antenna co-operates not with one, and with five antennas which are settling down on the given floor. Between the antennas located on different floors, it is possible to neglect communication because the narrow diagram of antennas orientation in a vertical plane. Considering that fact that each of antennas will receive signals from five nearby antennas two of which will defend from it on 1m, and three more – approximately on 2.0 m, we will reduce losses on 4 dB. We will definitively receive that the size of a signal accepted by everyone antenna will be only on 14 – 4 = 10 dB less level of a signal which it radiates. This signal is perceived by the terminal transmitter cascade as the signal reflected from load (as at high VSWR of load) and can cause unstable work of the amplifier.

If the hexagon party in which tops antennas are placed to increase, for example, to 2m level of received power will decrease to – 16 dB. Thus dimensions of antenna system considerably will increase. It is visible that increase in the linear sizes ineffectively. It will be much more effective application of the ferrite gate which can provide an outcome 20 dB and more. Thus matched load of the gate should dissipate constant power not less than 100 mW.

Certainly, such calculation has estimated character and shows only the tendency of antennas interaction in system. Character of antennas interaction depends not only on distance between them, but also from their design and the sizes, and also from wavelength. At interaction in a near antennas diagram of an orientation zone can be deformed, and already it is impossible to consider their gain factors as constants. For certain type antennas mathematical models of interaction in a near zone which will yield more exact result can be created and will allow to choosing the most optimum design of antenna system.

The second method of an interconnection between antennas reduction is diversity them on a vertical. Thus because of a considerable quantity of antennas the vertical size of such antenna system will be big, shadowing from a mast construction on one of radiation direction is considerable. There can be difficulties in system service. In any case the antenna design is a compromise between shadowing and reflections possibility occurrence from outside constructions of a tower and power losses of a signal in the antennas located in the same plane.

As all transmitters (all 12) work on different frequencies, but in one frequencies band all of them radiate extra band noise and disturbances local oscillator signals and image frequencies which are integrated in the given band. Total all these signals power which is radiated by 12 transmitters, will be accordingly on 11 dB more than the power of parasitic signals radiated by one transmitter. Thus, we will be compelled to toughen requirements on parasitic radiations value for each transmitter on the same 11 dB.

The block diagram of the Transmitting Complex is shown in Fig. 3. The equipment most part here is placed in a water-proof case which is completed by the thermostat and fan system. The signal received from the optical receiver (which also can be placed in a case) represents a group multi-channel signal in which channels can settle down any way in a frequencies range.

The power division of an input signal between Processors is made by means of loop back inputs of Processors in which the signal part branches off in the corresponding Processor, and other signal arrives on an input of the following Processor. Thus signal losses make 1.5 dB on each connection. That the difference in levels of signals on an input of the first and on an output of 12th Processor would not differ strongly (on 18 dB), the signal preliminary divides on two equal parts with the help of splitter, and then arrives on groups of 9 Processors.

Thus differences in levels decrease to 9 dB. So we save a stock on adjustment for the input scheme of an ALC. From outputs of Processors signals arrive on BPF with which help the channel filtration in an 8 MHz band is carried out that allows to reduce level of extra band interferences and noise.

Power supply on BUC moves on radio-frequency cables. Injecting of supply voltage in all 12 cables is made in the Crossover.

In table 2 advantages and lacks of the given architecture are specified.

fig.2 Losses on a line in a mode of “line-of-sight» (LOS) and «non line-of-sight» (NLOS).

The given signal should be processed by firm Televes Processors UHW. With their help channels are grouped in frequency in a certain order with a step of 10 MHz.

Fig. 3 The basic architecture of MMDS Transmitting Complex.

From Table 2 follows that to some parameters BUC increased requirements are shown. They are caused by two factors:

1. Application of modulation COFDM;
2. Coupling of antennas in system and features of signalling mode.

Table 2. Advantages and lacks of the chosen Transmitting Complex architecture.

Modulation COFDM in itself demands performance of some especial requirements.

These are such requirements:

1. Suppression of image frequencies – not less than 60 dBc.
2. Phase noise level of local oscillators at retune from carrier on 10 KHz – no more – 95 dBc/Hz.
3. The stock on power concerning a power average level – not less than 10 dB (PAPR = 10 дБ).

The requirements caused by features of antenna system work the following:

1. Noise power, disturbances, and parasitic products (ingress noise) – at level -11 дБ from their level for a case of one transmitter and one antenna use.
2. Power the local oscillator on an input is equal to power of the usual transmitter a minus 11 dB.

The Block diagram of declared system (the Variant 1).

The tentative estimation of a 12 single-channel transmitters BUC1 – BUC12 total cost with output power PCH = 1W shows that this cost more low, than cost of the group transmitter with output power P1dB = 300 W. Therefore point 1 in section of Table 2 “lacks” becomes one of advantages.

The lacks concerning points 3 and 4 are essential, and for their overcoming in the scheme resulted earlier it is necessary to incur considerable expenses. Therefore in the declared device it is offered to refuse signalling of separate channels on IF on coaxial cables. Instead it is offered to apply the multi-core fibre-optical cable which quantity of veins corresponds to quantity of channels N.

The block diagram of declared system is shown in Figure 4. The design of an equipment radio-frequency part and its elements remains without changes in relation to shown on Fig. 3. In the device are applied N omni-directional antennas (ANT1 – ANTn), N transmitters in the form of powerful upconverters (BUC1 – BUCn) p. 2, crossover N – channels p. 3 and N bandpass filters (BPF1 – BPFn) p. 4. On it similarity to earlier resulted scheme comes to an end.

Other part of a complex works as follows:

Signals of separate channels on IF having modulation QAM64 (DVB-C) or COFDM (DVB-T), arrive on inputs N of optical transmitters p. 7. Here they will be converted to an optical range and transferred on separate veins of a fibre-optical cable p. 6,

Which connects a studio part of a complex to that its part which is placed at tower top (in an installation site of a radio-frequency part). This part begins with single-channel optical receivers p.5 which will convert optical signals back to signals IF.

Fig.4

At the expense of signalling on a fibre-optical line all problems connected with a signal losses will be removed and also high noise immunity is reached. The distance on which the signal on fibre- optic cable can be transmitted, can reach 15 Km and more.

Thus, the main differences of declared system from existing will be the following:

1. Use of single-channel transmitters signals frequency multiplexing method in the transmitting space (on-air) by means of omni-directional antennas system.
2. Separate channels signalling from a complex studio part to its part placed at tower top, by means of the multi-core fibre-optic cable including in the design a conductor, serving for supply voltage giving from the power supply unit 8 on a complex radio-frequency part and optical receivers. Such construction allows to signals transmit on the big distances and excludes accumulation of noise and intermodulation products on fibre-optic cable line.
3. Signalling on the big distances possibility reached at the fiber optic cable use and maintenance thus high noise immunity in the industrial disturbances conditions allow to construct on the given Base stations basis a single frequency synchronous broadcast network (SFN) for each of multiplexing in the propagation space channels.

Thus signals from the network Central station (the Studio complex) are transmit to network Base stations on fibre-optic cables that allow to constructing a single frequency synchronous broadcast network for each of channels.

Besides, as delays by transfer on fibre-optic cable on distances of several tens in Km are very small and can be in advance defined, and the reflected signals are absent, the all network synchronisation is reached at the Central station by delay dispersion correction in each of channels. At the big network sizes it can give the big economic benefit as the corrector quantity will be minimal.

The declared system block diagram (the Variant 2).

The base station block diagram variant 2 assumes use in networks in which for any reasons fibre-optic cable lining for the Central station with Base stations set connection is impossible. In such networks instead of fibre-optic cable it is possible to use simplex radio relay communication lines (RRL). By multi-channel group signal transfer on RRL the frequency multiplexing, but reached on PHY level, also is used. Signalling on RRL and an broadcast Base stations is made with use of various standards (DVB-S – on RRL and DVB-T – for broadcast Base stations), therefore in signals processing paths it is necessary to establish the transmodulators QPSK/COFDM block (5 in Fig. 5) in which transport streams processing is supposed. Therefore synchronisation SFN in each channel should be made already at Base stations, and at the Central station pilot-signals are entered.

Designations on the block diagram:

1. The slot-hole omnidirectional antenna.
2. The Powerful Upconverter (BUC).
3. Crossover N – channels.
4. The channel bandpass filter (BPF).
5. The Block from N transmodulators with synchronisation schemes and with a support on signals GPS.

The system works as follows. The multi-channel group signal which for the given Base station is formed by the Central station, is received by receive RRS antenna 7 and will be converted by the downconverter 6 in an intermediate frequency group signal. Signal IF moves on the transmodulators block 5 inputs. In it separately for each channel transition from modulation QPSK to modulation COFDM and synchronisation with corresponding symbols COFDM transmitting by other Base stations in a network is carried out.

In the channel correction block the accepted pilot-signals are analyzed. By this analysis results a communication channel transfer function is estimated. Then channel correction is carried out – everyone carrier signal is multiplied by the found channel transfer function value for this carrier. In the following block the second (internal) interleaving and assemblage deinterleaving are carried out – operation, return to bits apportion on symbols. The bits sequence which arrives further on the errors correction block, similar to the corresponding block of satellite digital TV receiver as a result turns out.

From transmodulators outputs the IF signals, having passed channel BPF, move on powerful upconverters 2 (if frequency conversion is not required also transfer it is carried out on the same frequency on which modulation in the transmodulators block is made, frequency converters are replaced with power amplifiers). The gained radio frequency signals are radiated in an air by omni-directional antennas 1.

For the given variant basic novelty consists only in frequency multiplexing in the transfer space application.

Fig.5

Gained effect: The general system cost decrease, reliability increase and high noise immunity achievement.

Abstract

Expansion of a user’s stations receivers dynamic range at the expense of their gain factors adjustment and introduction of user’s stations receivers RF paths monitoring in system MVDDS carried out with use of direct and return data transmission own wireless network channels.

The required dynamic range of Central (Base) station receivers reduction by posts of video information gathering transmitters output level control with using the own wireless data transfer network downlink and uplink channels.

A scope

The given technical decision concerns radio engineering, more precisely, – to a broadcasting, to a video information gathering (video surveillance) and data transmission in borders of a certain geographical zone on district. System UWMS which is a prototype of patented system UWMS-R (“Rain”) represents a version of system MVDDS which is added by a video information gathering system. In it range Ku is mainly used. For example, for downlink the occupied frequencies band is equal 800 MHz. The band for uplink and a video information gathering system also can reach to 800 MHz. These bands shouldn’t be blocked with each other. On the contrary, between them some gleam is desirable. Range Ku is lowest of frequencies range in which allocation enough wide frequencies bands for direct broadcasting and data transmission channels, and also for return data links and video information gathering system channels is still possible. The given ranges it is used by systems MVDDS on a secondary basis as all of them or their considerable parts coincide with system DBS working ranges. These frequency ranges is boundary from the point of view of losses in hydrometeors as on frequencies above 10 GHz growth of a radio signal propagation losses to a rain zone (see Fig. 1) begins. Presence of the big losses in hydrometeors demands from direct and return receivers channels the expanded dynamic range on received signals levels for which achievement in system special measures should be taken.

Absorption in a rain

From Figs. 1a and 1b it is clearly visible that losses of a signal at the expense of absorption in a rain strongly depend on frequency. On frequencies below 5 GHz these losses in most cases can be neglected. But on the fixed communication and broadcasting lines working on frequencies above 20 GHz losses in a rain become a primary factor limiting the communication distance.

Naturally, losses in a rain depend on its intensity. In a zone of intensive rains on the foreground there is a peak intensity of a rain which is observed duration 0.1 % of time that corresponds to usual value of a line readiness 99.9 %.

It is much more important than the general annual norm of deposits. Peak intensity strongly depends on a geographical zone. In droughty regions intensity of a rain can to make some mm at hour (zones of violet color in Fig. 1с). In regions with very intensive deposits peak values of intensity can reach to 150 mm/hour (red zones in Fig. 1с correspond to intensity of 40 mm/hour and above).

ITU recommends methods for an exact prediction of losses in a rain. We will try to make rough calculation on the basis of materials available in the literature for a likelihood component of signal attenuation in deposits. All calculations for communication systems can be conducted taking into account hourly average distributions of rains intensity for the worst month of year.

a)

b)

Fig. 1 Dependence of loss factor γ on frequency:  a) for frequencies below 10 GHz; b)for frequencies above 10 GHz.

Fig. 1с A parity of loss factors for various geographical regions (source ITU-R).

The loss value at absorption of a radio signal by hydrometeors in dB is defined under the formula:

V=-y*Ref

where:

γ- loss factor, dB/Km,

Ref -effective length of a line (Km) on which the loss factor is approximately constant and  equal γ.

From Fig. 1b we find that the loss factor on frequency 11 GHz for region with deposits intensity of 50 mm/hour is equal about 2 dB/Km. It means that the stock on loss in rain on a line of 15 Km should be equal 30 dB.

Fig. 1b also convincingly shows that application of broadcasting and data transmission systems working on higher frequencies than applied in patented system in regions with such amount of precipitation in general is impossible.

Other factors influencing on input dynamic range of receivers used in system.

Output power level of Central Station each sector transmitter has the fixed value. This value gets out from a calculation of the minimum necessary signal/noise rate (SNR) maintenance for the most remote station of the subscriber under the worst reception conditions.

Fig.2 «Point–to-multipoint» network structure with spatial channels division on sectors within a service zone.

UWMS-R is fixed communication system, i.e. position in space of all subscriber’s stations concerning the system Central (Base) Station (CS) is in advance known. We will assume that the radius of CS service zone is equal 15 Km (r3 in Fig. 3), and most near placed subscriber’s stations are placing from CS on distance of 150 m (r1 in Fig. 3). Then the relation of lines lengths of distribution for the station which are on the brink of a service zone, and station which is from CS on distance only 150 m, will make 100:1. Expressed in dB the relation of received signals powers for these stations will be equal 54 dB (almost a mode to “direct visibility», but taking into account the city propagation environment). This dynamic range component on receiver’s inputs is a constant and practically doesn’t depend on time. If to consider losses in a rain which are a variable component of a dynamic range accepted by user’s stations and the Central station of signals possible difference in power levels on user’s stations receivers inputs and video information gathering system CS receivers inputs will reach 84 dB.

The method which is used for increase in a dynamic range on a receiver input more often is application AGC in the receiver. As receivers in a broadcasting part of user’s station and in a CS video information gathering subsystem the standard tuners (set-top box) standard DVB-S are applied in systems DBS. The range of admissible signals levels on tuner DBS input at work in a land broadcasting system is usually equal from – 50 dBm to – 20 dBm that corresponds to AGC depth nearby 30 dB. Some reduction of adjustment depth in AGC scheme rather 40 dB which correspond to receiving of satellite broadcasting channels speaks higher level of own land broadcasting systems receivers noise concerning noise in systems DBS because of what the bottom level of an adjustment range raises approximately on 10 dB, and the adjustment range decreases to 30 dB. But it is obviously not enough this AGC range for full indemnification of all receiver input signal level range, which as it has already been told, can reach 84 dB.

Fig.3 A necessary user’s receivers dynamic range determination.

A dynamic range expansion on a receiver input in UWMS-R.

In UWMS-R for partial indemnification of such big difference in received signals levels which is peculiar both to receivers of user’s stations, and concerning to CS to a video information gathering system receivers the method of a user’s stations parabolic antennas corresponding gain factors choice (diameters of mirrors), and user’s stations transmit and receive microwave converters and video information gathering posts transceivers microwave transmitting converters gain factors can be applied. Such adjustment is carried out in transmit/receive microwave heads of user’s stations and can be realized at the expense of the additional AGC loop covering high-frequency cascades of receivers. AGC Voltage simultaneously can be used and for adjustment on the same value the transmit/receive heads transmitting parts gain factors that is possible thanks to similarity of channels of reception and transfer. Such method is simple enough, but has essential lacks. The reception part of microwave transmit-receive head accepts not only broadcasting signals, but also a signal of a direct information channel (downlink). At gain factor adjustment the priority should be given signals of a television broadcasting as they demand transfer to a mode of real time, and admissible at their reception errors factor on two order more low than required for correct reception of an information channel signals (10-8 against 10-6).

If all adjustment in broadcasting channels to concentrate in user’s station it will be impossible to supervise quality of broadcasting signals reception by it operatively, being on CS. At the same time, one of important MAC components in modem WMTS is the quality management program (QoS) which allows to control by work of data transmission network flexibly. The similar system is necessary and for broadcasting channels.

The second lack peculiar to gain adjustment which is completely concentrated in user’s station, is very big complexity and duration of all system installation process. It will be necessary to establish threshold values for AGC in each of transmit/receive microwave heads individually taking into account a distance to CS that at a considerable quantity of subscribers a lot of time will demand. In the absence of all system work monitoring on CS it is impossible to react operatively to deterioration of reception conditions for separate user’s station and to interfere with a mode of its work.

Therefore management in values of gain factors both receivers, and transmitters it should be made remote and automatically from Central Station hardware.

At AGC and a method of remote gain factor adjustment of microwave transmit/receive head receive and transmit parts use in the receiver (DVB-S set-top box) the general indemnification of levels difference will make 64 dB. To full indemnification doesn’t suffice still, at least, 20 dB. The further indemnification is offered to be carried out at the expense of a service zone division concluded in sector with a corner of a beam 360 deg./N and limited by radiuses r1 and r3 on two parts, namely – between r1 and r2, and also between r2 and r3 (Fig. 3). In a near zone which is limited by radiuses r1 and r2 as a part of the user’s station equipment the antennas which gain factor on 20 dB low than at antennas of the stations located in a distant zone that limited in the radiuses r2 and r3 are applied.

Character of signals levels change that received by user’s stations is shown on curves in the bottom part of Fig. 3. The curve 1 shows dependence of signal level on inputs of the user’s stations receivers that radiated by the CS transmitter only from distance to CS at power level on an output of CS transmitter corresponding to power which is necessary to obtain in the most remote user’s receiver minimum SNR plus minimum in a rain loss on the maximum removal from CS. The curve 2 shows dependence of signal level on distance to CS taking into account losses in a rain which if they are expressed in dB are proportional to distance to CS. The broken line 3 shows dependence of power level on an antenna input-output of the user’s station microwave transmit/receive head taking into account change on 20 dB gain factors of antennas. In a distant zone the curve 3 merges from a curve 2. Thus power difference on antenna inputs of microwave transmit/receive heads is equal 64 dB. Thus, the reception user’s converters gain factors change value minus receivers (tuners) AGC ranges change should will is equal 34 dB. By television signals transfer the direct broadcasting channel and the return channel of a video information gathering system are similar as use identical modulation type and the same channel band. For reduction of the signals received by downconverters 8 (Fig.4) dynamic range and receivers (tuners DVB-S) of a video information gathering system transmitters gain factors should be changed to the same value as the gain factors of their reception converters.

That such system successfully worked it is necessary to enter into it the feedback channel on level of a signal received by user’s station. As the physical information transfer channel about level of a signal received by user’s station it is the most convenient to use a return data link (upstream) an information part of system, and for management in gain factors of user’s station microwave receive/transmit heads receiving and transmitting converters and transmit/receive blocks of a video information gathering posts – a direct data link. For this purpose it was necessary to make essential changes to the block diagram as CS sectors, and in the scheme of user’s stations and the Posts of a video information gathering.

Changes in the scheme of the Central Station

The essence of the changes brought in the UWMS block diagram is explained by Fig. 4 on which UWMS-R block diagram is represented.

UWMS-R which represents MVDDS united with a video information gathering system consists of following basic elements: the Central Station 1, a video information gathering system 2, and user’s stations 3.

The Central Station (CS) 1 consists of the segments 4 which quantity N depends on quantity of CS antenna system sectors (from 1 to 8 sectors). Each from segments 4 consists of the sector antenna 5 which on an output – input is connected to a diplexer output 6 which on an input is connected to the upconverter 7, and on other input – with the downconverter 8. The downconverter is connected by output 8 to the block of downconverters 9 which is connected by N outputs to the modem of the Central Station (WMTS) 10, and by an output is connected to a video information gathering system receivers.

Fig.4 System UWMS-R block diagram

The modem is connected by input-output 10 to the switchboard 13 which is connected by one of inputs-outputs to the monitoring and management block 14, by other input-output is connected to one of inputs-outputs of a digital platform 15, and by an output is connected to an input of the upconverter 11. The upconverter is connected by output 11 to one of combiner inputs 12 that is connected by other input to one of power divider outputs N 16, and by an output is connected to the upconverter 7 which is connected by an output to diplexer input 6. The digital platform by N inputs-outputs 15 is connected to switches 12 of N CS segments 4, and by an output is connected to the main CS computer (server) which has connection to external distributive networks. The N multichannel power divider by it outputs 16 is connected to combiners 12 of N segments 4, and by an input is connected to the multichannel combiner 17 which by N outputs is connected inputs with N inputs of remultiplexing station modulators.

The video information gathering system 2 includes a post of a video information gathering 18 which is connected through radio – or the cable communication line with transmitting stationary points 19 or only on radio lines with mobile points of a video information gathering 20, and on a radio channel is connected with CS 1 by means of the transmit-receive block 21.

All data transmission network operating mode organization is assigned to CS modems 10 which quantity is equal to quantity of segments 4. Traffic of separate modems 10 unite CS digital platform 14, and the incorporated traffic arrives on the computer (the main computer of system – the server) which provides interaction with external networks of data transmission.

The scheme of the UWMS-R Central station differs from the system scheme – prototype UWMS those two new elements are entered into its structure – the switchboard 13 and the block of monitoring and management 14. The switchboard 13 is intended for allocation from the general data flow of that data which concern an auxiliary network of data transmission of a control path in gain factors of type USn user’s stations receiving and transmitting parts microwave transmit/receive head and video information gathering posts transmit-receive blocks and quality assurance of broadcasting signals accepted by them. In the monitoring and management block all functions of management and control that allows the operator to supervise a current condition of a network are concentrated. Management in gain factors of receiving and transmitting converters of user’s transmit/receive heads and transmit/receive blocks of a video information gathering posts is carried out in an automatic mode by means of the special program containing in the CS block of monitoring and management.

User’s station USn

User’s station USn (Fig 5) consists of the antenna 1, the microwave transmit/receive head 2, the transceiver 3, tuner DVB 4 and the user’s modem (CPE) 5. On the microwave transmit/receive head input is established the polarization selector 6 which on an input-output is connected to the transmit/receive antenna 1, by one of outputs is connected to the filter 7 which is connected by the output to an input of the low noise amplifier 8 which on an output is connected to one more filter 9 which on an exit is connected to an input of the amalgamator 10. The amalgamator is connected by other input to one of exits a heterodyne 11, and by an exit is connected to an input of the amplifier with gain control 12. From an exit of the gain control amplifier the signal on a coaxial cable arrives on the transceiver 3. On other cable from the transceiver 3 signal arrives on an input of the microwave transmit/receive head transmitting parts commutator 13 (Switch), and by other commutator input is connected to one more output of a local oscillator 11. The commutator output 13 is connected to an input of the filter 14 which is connected by the output to an input of the amplifier with gain control 15 on which input and on an input of the gain control amplifier 12 from the transceiver the signal of management in gain factor is given. The output of the gain control amplifier 15 is connected to an input of the power amplifier 16 which is connected by the output to an input of the polarization selector 6.

The signal from a reception part of the transmit/receive head arrives on transceiver 3 diplexer 17. One of diplexer outputs is connected to an input of the downconverter 18 which is connected by the output to an input of the multiplexer 19. The multiplexer 19 is connected by input-output to an input-output of the user’s modem 5, and by an output is connected to an input of the upconverter 20 which is connected by the output to a microwave transmit/receive head 2 transmitting part. The user’s modem is connected by 5 other input-output to an input-output of the commutator (switchboard) 21 which is connected by the second input-output to an input -output of the coder/decoder 22 which is connected by an output to control inputs of amplifiers with gain control 12 and 15 of microwave transmit/receive head 2. The second diplexer 17 output is connected to directed coupler 23 input which is connected by the output to an input of the detector 24, and the detector 24 is connected by output to an input of the coder/decoder 22.

Directed coupler 23 by it output is connected to an input of the tuner 4 from which the signal moves on the television receiver. The commutator (switchboard) 21 has an input of peripheral user’s devices port with which help it is connected to the user’s computer or to a data transmission network.

Defining elements for user’s station ASn are:

the switchboard 21, the coder/decoder 22, the detector 24 and the directed coupler 23. In directed coupler 23 broadcasting part of the signal received and converted to an intermediate frequency signal in microwave transmit/receive head, branches off in the passing power detector 24. The signal from the detector arrives in the modem 22 in which it is digitized. The modem forms the data for transfer on a network of management and monitoring for their inclusion in a return data link through the user’s modem 5, and also accepts and will decode the data received from the user’s modem 5 on direct data link. On the basis of the management commands received from CS on a direct data link the management signal intended for adjustment gain factor of microwave transmit/receive head 2 amplifiers with gain control 12 and 15 is formed.

Fig. 5 User’s station USn block diagram.

The transmit/receive block of a video information gathering system

The transmit/receive block of a video information gathering system (Fig. 6) consists of following elements: antennas 1, the microwave transmit/receive head 2, the transceiver 3, and the user’s modem (CPE) 5. The microwave transmit/receive head 2 has no differences from applied as a part of user’s station USn. The transceiver 3 has following differences (elements of similar appointment are numbered equally) concerning the same block of user’s station USn:

• It is excluded directed coupler 23;
• The commutator (switchboard) 21 is excluded;
• The tuner 4 is excluded;
• The combiner 25 is added.

Fig.6 A video information gathering system transmit/receive part.

The tuner 4 use as a part of the video information gathering post equipment there is no necessity. Also there is no necessity in directed coupler 23 as all broadcasting signal goes to the detector 24. As there is no necessity for connection of the peripheral equipment of the user, there is no switchboard 21. The user’s modem 5 is used only for reception management, and control signalling. After reduction of all signals arriving on a video information gathering post from the video information gathering points, to one kind, their coding, multiplexing of the received transport streams in a uniform transport stream and modulations by this stream carrier on intermediate frequency the modulated signal moves on the combiner 25. In it unites with a return information channel and the microwave head with which help it is transferred on CS moves on transferring part microwave transmit/receive head.

Application instead transmitter of the video information gathering channel the transmit/receive block allows to carry out adjustment from the Central Station on a direct data link of transmit/receive transmitting part gain factor and level of its output power that allows to reduce at reception of signals from several video information gathering posts levels difference on an input of CS receiving converter. In this case also antennas, at least, two types are used.

User’s station US1

In UWMS-R application of user’s stations US1 which have no return data link is supposed and consequently aren’t subject to control and management from CS. The loop of automatic gain control (AGC) is applied to maintenance of a necessary dynamic range on an input of this type user’s stations in their receiving converters which supplements AGC of receiver DVB-S.

Also antennas of two types with different gain factors are applied.

The UWMS-R operation description

In following sections the work description of UWMS-R is given.

Formation of a television broadcasting signals: Signals of TV broadcasting are formed by remultiplexing station (in drawing it isn’t represented). The remultiplexing station usually represents a teleport which receives signals of satellite, cable, wireless TV, and also signals from local studio. On CS these signals are properly processed. This processing includes decoding of those signals which are coded by systems of conditional access of satellite and cable TV operators (descrambling), transport streams remultiplexing for the purpose of new multiplexes of TV programs formation and scrambling these streams by own system of address coding. After the specified operations necessary for scrambling DVB-S streams formation the received data flows are sent on modulators on which outputs are generated carrier modulated by multiprogramme TV signals.

The modulated carriers unite in a multifrequency group signal by CS multichannel combiner 17. Further the group signal divides on power on N parts (by quantity of system segments) by means of a power divider 16. On outputs of a power divider 16 it is received N copies of a group signal, each of which goes on the combiner 12 one of CS segments 4. After summation with a signal of a direct data link this signal will be converted and amplified by the upconverter 7, then arrives on an diplexer input 6 and, having passed it, is radiated by the sector antenna 5 in the form of a beam in width 360grad/N (where N – quantity of sectors of antenna system).

Formation of a direct data link (downstream): The downstream is formed by a transmitting part of the CS modem 10 (WMTS). In it DVB data packages with time division (method TDM) modulate preliminary established carrier and forming a direct data link. Further this signal will be converted to a necessary frequencies range, amplifies and summarized by means of the combiner 12 with broadcasting signals forming a full group signal of the direct channel. Further it will be converted and amplified by the upconverter 7 and, having passed through diplexer 6, is radiated by the sector antenna 5 in the form of a beam in width 360grad/N (where N – quantity of antenna system sectors).

The signals are received by user’s stations USn 3 and by transmit/receive blocks of a video information gathering system posts.

Transfer of upstreams: Upstream signals are transmitted by stations of type АСn and transmit/receive blocks of a video information gathering system posts in a direction of CS sector antenna. Methods of frequency and time multiplexing (method FDMA/TDMA) are thus used. At use of this method of multiplexing quantity АСn that works on one frequency and transfers messages in the form of packages at the command of the CS modem 10. These commands are built in structure of the uplink channel of the data in the form of the special channel (control path). Such way reaches frictionless work of type АСn stations, and also monitoring and management of a video information gathering system posts transmitter work by transfer of upstream data packages and signals of system of gathering of a video information gathering system by them. By such principle the work of similar АСn stations which work on other frequency, and also those from them which belong to CS segments 4 with numbers 2 … N are realized.

Signalling by a video information gathering system: A video information gathering system has two-level structure. Necessity of such construction is caused by that the signals transferred by stationary 19 or mobile 20 video information gathering points can correspond to different standards, for example, DBS – for analogy points and DVB-Т – for digital. Besides, for signals of the first level it is difficult to receive sufficient range by transfer which would allow to transmit directly a signal on CS because a video information gathering points transmitters limited power (especially mobile), a low placement of transmitting antennas, and also difficult radio-waves propagation conditions (absence of “direct visibility», presence of a great reflected signals number and etc.). Inclusion in system structure of a video information gathering posts some quantity which placed so that for them the mode of “direct visibility» with CS was provided allows to solve this problem. The receivers 18 which are a part of the video information gathering posts transmit/receive block 21 (Fig. 4) receive and process the various signals arriving from a video information gathering points, and will convert them to a uniform kind (to a kind of DVB transport streams – TS). Further these TSs are multiplexing in the uniform datastream which modulates carrier on intermediate frequency. Then this signal arrives on the transceiver and microwave transmit/receive head of the transmit/receive block 21 in which it will be upconverted on frequency and amplifies for the further transfer on a radio channel in CS direction.

On each CS segment 4 signals from UСn and video information gathering posts 18 which are located in sector of the CS antenna 5 arrive. Having passed diplexer 6 the signals received by the antenna arrive on the low noise downconverter 8 in which they amplify and will be converted to signals of intermediate frequency. Signals of intermediate frequency arrive on a multichannel power divider of the converter 9. This divider has outputs quantity which is equal to quantity of CS modem 10 inputs plus one more output from which one of the received signal copies goes on a video information gathering system receivers (in Fig. 4 aren’t represented). As these receivers usual tuners DVB can be used.

A control system of a network information part.

The control system of a data transmission network (NMS) is concentrated in DOCSIS WMTS. It supervises serviceability and the UWMS-R information part parameters by means of monitoring and management systems. Functions NMS include network operating modes control, administration, network service, and user charge levy from network users.

The sizes of a service zone usually depend on system gain of the radio-frequency equipment and transmitting and receiving antennas, meteorological characteristics of region in which system UWMS-R is located, and also the real relation a signal/noise reached in system. In general the radius of a service zone should be more 10Kм.

Though spectrum UWMS is wide enough in comparison with the frequencies bands defined for radio lines of type a point-point (PTP) and a point-multipoint (PTM) on lower frequencies, in system, except time and frequency, is applied as well spatial division of the signals arriving from user’s stations, to increase in their quantity and network information capacity.

The increase in number of sectors increases CS cost as transceivers should repeat for each of sectors. However advantage of sector construction is that application of antennas with higher degree of a directivity which occurs at replacement of the omnidirectional antenna on sector antennas system reduces possibility of the effects coupled with a multibeam propagation mode occurrence, and thereof, reduces an intersymbol interference (ISI).

But decided advantages of sector antenna system construction is substantial growth of a data transmission network subscribers quantity and a video information gathering posts quantity at the expense of spatial division and possibility of a frequencies reuse.

The downstream (the direct channel): The access scheme for the direct channel – TDM with frame length from 3 ms to 6 ms. The channel pass-band is set in limits from 8 MHz to 20 MHz.

A transport stream frames contain time slots set which can be divided on starting slots and slots of direct access. To simplify data-handling procedure in CPE, it is necessary that the relative quantity not accepted slots in a frame are no more than 7 %. At transfer data rate in a downstream direction 41Mbps it corresponds to 50 ATM cells or 14 packages of MPEG2-TS in a frame in 6 ms. Everyone CPE can then to receive approximately to 3.5 Mbps.

The central station is capable to transfer of several channels simultaneously. However CPE can accept only one channel. It can be switched to various frequencies, but such switching can demand a time interval having duration that equal to several time slots.

The frame structure will be coordinated with MPEG-2 Transport Stream. The MPEG2-TS MUX package contains 188 byte into which enter one byte of the synchronization, three bytes of heading containing the service information, the information about scrambling and management, and the subsequent 184 bytes MPEG-2 or the additional data. Packages scrambled with use of pseudorandom binary sequence (PRBS) with the period of 1503 bytes that corresponds to 8 packages. Synchronization bytes are not scrambled. The first byte of synchronization is supplemented.

According to specification DOCSIS channel coding assumes 5 components: scrambling, interleaving, Reed-Solomon block coding, convolution encoding and, at last, constellation formation (mapper).

The direct channel uses the norms defined by standards DVB for satellite services in ranges of 11 GHz and 12 GHz. The system is optimized for an access method on one TDM carrier, but allows to apply and the multifrequency access (FDM) scheme. As typical data rate the multiple by 8 Kbps rate is defined. The frame structure is equivalent to specification DAVIC and contains 188 byte.

The upstream (the return channel): The access scheme in the return channel is TDMA. A frame length is the same as for the direct channel, i.e. between 3 ms and 6 ms. CPE regulate a choice of a package transfer time moment in an return direction before coincidence to slot borders in a frame of an upstream on CS at the set admission on time. Its accuracy is defined by a difference in a propagation delay that is corresponded to radius of a service zone. The control system of a network distributes set adjacent time slots so that to generate longer slots the network access that preventing collisions by transfer of TDMA package which can accompany access CPE to a network. Synchronization is reached thanks to that CPE adapts the transfer moment in reply to feedback by synchronization mistake until while this error doesn’t become less duration of one symbol in an upstream (a guard interval in a package has the duration equal to 4 symbols). The central station makes periodic inquiries about a synchronization error for achievement of necessary accuracy.

The package of the upstream data contains 68 byte. The upstream frame contains F slots where F depends on transmission data rates in an upstream. F slots are divided on request slots, direct access slots, and reserve time slots. The slots quantity parity each type is dynamic.

Shorted Reed-Solomon RS (204,188) code is chosen as a block code which is defined for an uplink. At entrance BER nearby 7*10-4 or less and at unlimited bytes interleaving the decoder should carry out QEF (quasi error free) an output at which BER makes from 10-10 to 10-11. Convolutional interleaver is just the same, as well as applied in a downstream under specification DAVIC (T=12, M=17), and also is the block coder. The block decoder should work at error rate on an input (BER) that equivalent to “the rigid decision”, between 10-4 and 10-2, and should provide BER nearby 2×10-4 or less.

The roll-off factor for the filter with the type characteristic «a root square of the raised cosine» is equal 0.35 that differs from specification DAVIC where it is applied either 0.2 or 0.35. At use of digital filter FIR it is possible to make alignment (equalization) non-linearity in the channel. This filter isn’t standardized therefore its kind will depend on concrete channel parameters. The modulation scheme is usual Gray-coded QPSK.

WMTS allows to controlling the power given by user’s modems, and at the expense of it carries out adaptive suppression of an ingression noise in the receiver in real time. Measurement and the analysis of the signal/noise rate in receiver WMTS is for this purpose made. On the basis of this analysis special commands for management of user’s modems transmitting parts are developed. Further the signal which has arrived in receiver WMTS is processed in an equalizer that allows to increase throughput of cable modems DOCSIS at the expense of granting practically in all cases of possibility of their work in a mode 16QAM instead of QPSK. The equalizer corrects a signal at influence on it frequency fadings, peak distortions, and also non-uniformity of a group delay. If nevertheless noise can’t be suppressed (for example, at very big level of ingression noise or a strong interference) WMTS can prevent consequences of noise influence at the expense of a modulation type change or transition in a frequency hope mode (mode CDMA).

For improvement of all modems DOCSIS parameters which work as a network part in WMTS it can be used the additional receiver that is included in parallel to four receivers which are intended only for a network subscriber’s service. This receiver gives to operators possibility of an operational administration in any of input ports parameters, without interfering thus with their work on servicing. For this purpose the additional receiver is connected to in parallel chosen receiver so the operator can measure the traffic and signal parameters in real time for any of functioning ports. Simultaneously, this receiver can have access to the network information and the full list of the cable modems working on any of receivers which is subject to monitoring. Thus, while any of receiver ports works at a total load, the additional receiver can increase access to other return channels by reception of tests for each of receiving channels and an estimation of their loading.

Auxiliary data transmission network for monitoring and management in gain factors of microwave transmit/receive heads up- and downconverters: The auxiliary data transmission network for monitoring and management in gain factors of active microwave transmit/receive heads up- and downconverters can be constructed as a usual IP-network which uses a wireless network of system UWMS-R data transmission as transfer media. On UWMS-R return information channels (upstream) the data intended for broadcasting signal level monitoring that received by user’s stations is transferred. This data is entered into the return channel by means of the commutator (switchboard) 21 (Fig. 5). At the Central station the monitoring data arriving from all active user’s stations on a modem WMTS 10 output (Drawing 4 see) separates from the given clients and goes to the block of monitoring and management 14. Here on the basis of the received data on certain algorithm management commands for each of user’s stations which by means of the switchboard 13 are entered already into a direct data link are developed and transferred on a radio channel simultaneously to all user’s stations which are in given sector. To reduce quantity of the information intended for transfer on the direct channel it is necessary to hand over only the information on microwave heads converters gain factor change. On an each of user’s modems (CPE) 5 output all these signals are present and arrive on the switchboard 21 (Fig 5) with which help the data concerning only to a control system separates. In the coder/decoder 22 the management commands concerning given user’s station will be decoded, and given user’s station USn microwave transmit/receive head up- and downconverters or video information gathering posts transmit/receive blocks control signal is developed.

Existing techniques level

System UWMS which represents interactive system MVDDS (multimedia system) combined with

a video information gathering system (video surveillance) which has two-level structure is known.

By means of the given system following functions are realized:

• Signalling of multiprogramme TV broadcasting;
• An exchange in an interactive mode the internet data and its appendices with User’s station set at use of own wireless return channel;
• An exchange in an interactive mode the internet data with corporate users on the allocated channels;
• Transfer on return channels, except the data, on the own frequency channels and in real time mode the multiplexes consisting of several transport streams which are formed by a video information gathering posts (top level of a video information gathering subsystems);
• TV signals transfer on wire and wireless transfer channels from a video information gathering points set (stationary or mobile points of cameras placement) on a video information gathering post (the bottom level of a video information gathering subsystems).

Prototype lacks:

1. The basic UWMS system lack is rather low level of user’s stations receivers and the receivers established in each of Central (Base) station sectors adaptation to the big range change of received by them television broadcasting signals and the signals transferred by a video information gathering system levels. This levels range is a consequence of distances from the Central station to the subscriber and a video information gathering posts locations wide spacing and also attenuation in a rain. The big levels change on receivers inputs in system UWMS can be partially compensated for account receivers DVB-S AGC and at the expense of antennas with various gain factors application that can appear sufficient in usual conditions. But in the conditions of intensive loss the deposits losses from which can’t be neglected for signals with the frequencies used by system UWMS the specified methods of received signals levels change (a dynamic range on a receivers input sizes) indemnification are obviously insufficient.

2. The second of essential lacks are great difficulties and expenses of time for system installation as each of user’s stations and each of the video information gathering posts transmitters demands individual antennas adjustment not only on a corner of a place and an azimuth at orientation to the Central station but also individual selection of antennas gain factors (diameters of reflectors).

3. System operation as at the Central station the information only about work of an information system part is accessible to the operator is complicated, and operator is not known about quality of television signals reception. At the same time, monitoring of television channels transfer is especially important as in system work TV broadcasting signals which should be transferred with bit errors rate no more BER = 10-8 should be priority. Such high BER the mode of real time demands by transfer both broadcasting signals and the signals transferred by a video information gathering system.

At the expense of what in the UWMS-R system these lacks are eliminated.

System UWMS-R differs that for the purpose of indemnification increased at the expense of losses in a rain a dynamic range on receiver’s inputs, except those measures which have been applied in system UWMS, following changes are made to it:

1. Into scheme system CS (Fig. 4) are entered the switchboard 13 and the block of monitoring and management 14.
2. Into the schemes of User’s stations USn microwave transmit/receive head 2 and a video information gathering post transmit/receive block variable gain amplifiers 10 and15 (Fig. 5) are entered.
3. Into the scheme of User’s stations USn transceiver 3 (Fig 5) the directed coupler 23 and the passing power detector 24 are entered.
4. Into the scheme of User’s stations USn transceiver 3 (Fig. 5) the switchboard 21 and the modem 22 are entered.
5. Into the scheme of a video information gathering post transmit/receive block transceiver (Fig. 6) the detector of falling power 24 and the coder / decoder 22 are entered.
6. Into the scheme of a video information gathering post transmit/receive block transceiver the combiner 25 is entered.

At the expense of the measures concerning points 2, 3 and 4 the increase in a dynamic range on the User’s stations of type USn receivers inputs is reached.

At the expense of the measures concerning points 2, 5 and 6 levels difference of signals which are radiated by transmitters of a video information gathering posts transmit/receive blocks transmitters reduction and, thus, reduction of a demanded dynamic range of the Central Station sectors 1-N receivers is reached.

Functioning of all system is provided with measures on point 1.

It is necessary to notice that in spite of the fact that regulation in system is carried out on the basis of powers measurement in broadcasting channels this regulation is very useful and by direct and return channels transfer of own data transmission wireless network as promotes reduction of a adjustment range in the user’s modem (CPE) that is especially important at work in mode TDMA.

The improvements brought in system UWMS-R allow it to keep working power in presence of intensive deposits but they are useful and in usual conditions as help to lower expenses for installation of system and to lower working costs.

CONCLUSIONS

Thus, the decision of the put technical problem probably only on the basis of the technical decision offered for system UWMS-R which will allow to use a system working in Ku band in regions with the big deposits intensity. However technical decisions used in declared system can give positive economic benefit and at system use in usual environmental conditions at the expense of decrease in expenses of time for installation and working costs. The given decision also can be useful in regions with slightly smaller deposits intensity but at system work in higher frequencies ranges.

Introduction:

Operators well understand importance of continuous subscriber base expansion which first of all can be reached due to cover zone expansion. Thus it is extremely desirable to have the centralized network with the only one Central Station (CS). Practically in all large cities there are rather densely populated suburbs, satellite towns and suburban settlements on which cable operators seek to expand a coverage area of the subscriber network. However often to deliver there the signal to the operator happens not so simply because of the high works cost on an optical fiber laying, difficulties to projects coordination and some other the reasons. In this article it will be discussed a question of these difficulties overcoming possible ways due to wireless decisions application. Our offers are based not only on the theoretical analysis, but also on examples of the real projects realized with our help by acting operators. In this article we will share experience of such systems creation.

Cable – Optics – RRL – the Broadcasting:

In the beginning some words about possible algorithm of the TV broadcasting cable networks development, about their history and prospects. There will be no statement wrong that actually each cable operator began the business just with a coaxial network development, on that he “cable” operator is. With fiber-optic communication lines development operators started using them for laying of the main lines, and over time – and for a signal distribution to the house. Advantages of fiber-optic in relation to a coaxial cable can’t be underestimated but fiber application as it was noted above isn’t always economically justified. In that case wireless means, and first of all LOS radio relay lines (RRL) can replace fiber. On modern RRL it is possible to transmit signals with difficult types of digital modulation which are similar to the DTV signals transmitted on cable networks (for example, QAM64). It allows to simplify and reduce the price significantly of a cable network signaling on long distances because in radio relay stations (RRS) on the transferring block input the group signal with Central Station (CS) simply is given, and on the reception part this group signal is used for the subsequent distribution. Earlier in case the regional cable operator wanted to expand a cover zone of the network on the neighboring settlement, in most cases it had to build new CS in this settlement. Due to RRS use there was an opportunity rather cheap to expand, scale and configure a cover zone. Especially as the method of a signal delivery to the subscriber remained habitual for all operators – on a cable network. Only a source of a signal is not CS, and the RRS receiver. Those from operators who to connection of the networks already applied RRS, understood what even need of obtaining permission to use of frequencies for RRL doesn’t outweigh all benefits from use of such technology for a network expansion. They were convinced that this procedure not such and difficult as can seem at first sight.  Point-to-point RRL solves a problem of connection between cable networks. However in certain cases the problem consists not only in signal delivery to the hubs, but also in creation of the distribution network. Sometimes expenses of time and funds for a cable lying on not really densely populated suburb aren’t justified, and at the same time “fixing” in this area is desirable and perspective and besides–urgent. How without excessive expenses to meet all these requirements? In such situation usually applied well all the familiar TV broadcasting technology – MMDS which works in the range of frequencies occupied also by mobile communication systems that causes difficulties at its introduction. By means of the broadcasting systems which equipment works in other available frequencies ranges, it is possible to cover with a signal all necessary territory. For this purpose it is possible to use the wireless repeater working in any available frequencies ranges from 2 to 30 GHz, i.e. actually to organize of your cable network signal delivery to the house of each subscriber without lying of cables in general. Installation of such system together with installation of intakes takes some days from subscribers. Thus subscribers of a wireless network, as well as subscribers of a cable network, use standard reception tuners as by wireless transfer all signal parameters – modulation mode, a signal scrambling system of conditional access, service table’s creation, etc remain. The final subscriber won’t feel a difference in connection. It should be noted only some complication of the subscriber equipment – for wireless reception rather inexpensive reception converter, the satellite antenna with necessary gain factor and a power supply injector will be necessary for the reception converter, i.e. actually a set for reception of satellite TV. Approximately so evolution of the cable operator network at expansion of its cover zone looks. The positive moment is that the described decisions are already realized and are operated, and the operator who has made the decision to introduce at similar system, won’t be a pioneer. Therefore in the following section we will tell about the principles of real systems creation.

Networks expansion primers:

1. Covering of suburbs. To us the CATV operator made an inquiry on production of the equipments set working in the frequencies range allowed for it which would intend for signal translation from its cable network on the nearby suburb since to develop there a cable network was economically inexpedient. The decision to cover with the signal consisting of 12 carriers, both the city and the suburb at the same time since and in city boundaries were at home yet not connected to its network was made. The broadcasting had to be carried out from a roof of Central Station building evenly in all directions (on 360°), covering all necessary territory. Shadow zones (sites in the general cover zone where the signal doesn’t get because of LOS mode lack) had to be served by micro repeaters (inexpensive low-power repeaters). Opportunity, as collective reception (one receive converter and the antenna on an apartment house or a little private), and individual reception for the private sector (one reception converter and the antenna for each user) was assumed. Thus in case of collective reception it is possible to apply more highly stable reception converters, i.e. more expensive, and for individual reception it is possible to propose the inexpensive available solution. This system was constructed and successfully brought into commercial operation. The signal covered the territory more than 10 km in the diameter, relaying of broadcasting signals in the shaded sites, collective and individual reception were realized. At hybrid network subscribers the same standard cable tuners and cards of conditional access system as well as at other cable network subscribers were installed. Thus, the hybrid cable network which has allowed the operator quickly to expand a cover zone of a network was created and to increase number of subscribers. Thus development of actually cable network was continued as on time expiration can prevent to switch nothing at the subscriber a wireless source of a signal on wire.

2. Covering of the neighboring settlements. This is example of other operator. Development of an existing cable network came to a standstill; almost all potential subscriber bases in this settlement were captured. And, as we know, it is impossible to stop in development in any way. Therefore the decision to expand network action on the neighboring settlements was made. In this situation, unlike the previous case, it was decided to go some other way. Since a large number of repeating and a signal transmission on a long distance was expected (because of a hilly cross-country terrain), it was necessary to apply more noise proof modulation with the best power parameters, than QAM64. QPSK modulation was applied, i.e. was actually decided to build a broadcasting network by the principle of MITRIS system (the simple table showing efficiency of use of frequencies bands depending on applied modulation) is given below. It allowed to develop quickly enough relay flights with broadcasting repeaters for a full covering a signal of the neighboring settlements. Thus subscribers could use a usual set of the reception equipment of satellite TV without any completions.

3. Application of a broadcasting/distributive network. We will give one more option of a hybrid network. Here the wireless network at the same time plays a role, both a distributive network, and a broadcasting network. The CATV operator constructed earlier independent cable networks in several neighboring settlements, but service of these separate networks for one operator was difficult. Association of networks in one with use of one general CS was required. The transformed network looked as follows: all settlements as well as earlier were served by the cable networks the signal in which arrived through a network of relay and broadcasting lines which at the same time covered the territory and broadcast a signal with QPSK modulation to a reception place. Here the signal with QPSK modulation was transmodulated in a signal with QAM64 modulation also moved in the CATV network. Thus, the operator obtained stable communication lines (flights between the transferring and reception equipment in wireless systems) between the networks with a simultaneous covering a territory signal for fast connection of subscribers to whom the cable network isn’t brought, kept all subscriber equipment and had to control only one central station.

In the examples given by us it is shown how it is possible to expand a cover zone due to interaction of wireless and wire decisions and to complicate a configuration of a uniform hybrid broadcasting network, increasing such way number of served subscribers and facilitating network service by the operator.

The table of a frequency resource use efficiency for two modulation types at a broadcasting of 200 MPEG-2 SD channels

From an economic point of view a system of digital multichannel TV broadcasting MVDS / MITRIS is one of the most effective and fast payback. Hundreds of MVDS / MITRIS operators around the  world receive evidence in this. The Company ROKS stands at the origins of this technology and can say with pride that this technology is the brainchild of Ukrainian engineers

So what is the main feature and attraction of building a broadcasting network by

MVDS / MITRIS technology?

• Head-end and the MVDS / MITRIS network is very flexible and easily scalable, at the initial stage of construction it makes your costs minimal, and with the development and expansion of customer base – increases the number of services and cover zone.
• Easy control over the subscriber base, through the use of a reliable system of conditional access and billing software – you know, and control each of your subscribers, providing them with that service, which he will choose, that is, in fact, you become a local “satellite operator”.
• The availability and low cost of user equipment – every operator knows the importance of this issue, because having a subscriber base of several thousand users, the overpayment in a few dollars per one unit of CPE evolves into a few thousand in wholesale purchase. In the case of MVDS / MITRIS system you cannot afraid because subscriber’s equipment is the usual set for reception of satellite TV!
• Providing the elective content (list of programs) to your subscribers (more than 100 programs) – with this advantage you’ll be out of competition compared to the satellite and on-air FTA broadcasting because you can give to your customers exactly that programs, about which they only heard and dreamed of getting them, and this is for a single payment from one hands.
• Improvement of our equipment has made it possible to use the system MVDS / MITRIS not only with QPSK modulation, but even QAM! This innovation allows you to significantly reduce the required frequency range!
• Wireless Technology – MVDS / MITRIS is a wireless system, that’s why by the pace of deployment you will be able to beat any competing cable operator, and get into the houses to which your competition can not even get close.
• Tried-and-true decision – deciding to become a MVDS / MITRIS operator , you will not be a pathfinder, because hundreds of operators around the world are successfully working with this technology for many years, stored extensive experience in operating the system, and we – the company ROKS – all those years we were developing and improving technology to offer it to you now.
• Permanent support – the company ROKS, as a developer and system integrator with extensive experience will never leave you one by one with your problems by providing advice and technical support.

Here are the 8 answers on the questions  “Why MITRIS? Why ROKS?”

Video Surveillance Systems

PJSC “ROKS” develops, manufactures, and installs the municipal level professional systems of video surveillance. Our systems of video surveillance have two levels: top (in Ku-band) and bottom (in S-band). At the bottom system level the video information gathering arriving from cameras of stationary and mobile video surveillance points on so-called video surveillance post is made. At top level signals which collect in video surveillance posts are transmitted in the Central station direction. Such technical decision allows to realizing such throughput of system which surpasses throughputs existing and perspective WLAN and is comparable only with throughput of FOLs.The Problems of existing video surveillance systems

The problem consists that all extended to today LANs including advanced of them – WiMAX, possess insufficient throughput for distributed video surveillance networks that created on their basis. Besides, all of them (both Wi-Fi, and WiMAX, and perspective LTE) have a slope of the traffic towards the direct (downstream) channel while a video surveillance networks demand, on the contrary, a slope of the traffic towards the return (upstream) channel on which the basic volume of a video information is transmitted while on the direct channel only management signals are transferred.

Conclusion. Construction of a professional wireless video information gathering (video surveillance) network on the basis of extended, and also perspective and specialized local networks isn’t expedient.

Professional wireless video surveillance network architecture

At a professional network design we suggest to refuse:

1) from a time duplex, having replaced its frequency duplex;

2) from TDMA mode in the return channel. All transfer time should be given transfer of one radio channel to a continuous mode. The increase of transferred television signals quantity is reached not at the expense of time division, and at the expense of digital multiplexing.

Certainly, such mode will demand use of the big frequencies band. Big enough band can’t be realized in those frequency ranges which are used traditional LAN, i.e. ranges L and S, and even C. We have stopped the choice on range Ku (more particularly, on a band 10.7 – 11.7 GHz), in which allocation enough wide frequencies bands are probably.

The main key features of a network offered by us:

Our network is two-level. It consists of top level which represents the fixed data transmission network consisting of the Central Station, constructed around system of sector antennas (having from 4 to 8 sectors), and sets so-called “Posts of a video information gathering (video surveillance)” which represent transmitters of the digital multiplexes including from 8 to 16 television programs of usual quality (SD). The main variant of network architecture assumes a configuration of type “star” in which video information gathering posts being in limits of the given Central Station sector immediately connect to her. Such architecture is most rational, as with its help the greatest throughput of a network is reached. However to realize it in the conditions of a big city without resorting to additional capital construction it is not always possible because of high-rise buildings which can get in way of the beams bridging a video information gathering post from Central Station sector antenna. In quality of a “spare” variant it is possible to apply “a treelike” configuration. In this case the network is designed in the form of a hub chain to which the branches bridging these hubs with posts approach. The Central Station is on the chain extremity. Such chains can be a little. A problem both “star” and “tree” is achievement of mode «line-of-sight» (LOS) for all transmitters and receivers in a network.

For unequivocal separation of posts on sectors the division of all available frequencies band into two parts (if all frequencies band makes 1 GHz half will be peer 500 MHz) is required. We are guided by standard DVB-S/S2 which assumes that a frequencies grid step of radio channels is equal of 35 MHz. Then in the designated frequencies band it is possible to place about 14 posts of a video information gathering. Through one sector the channels frequencies are repeat. At use of standard DVB-S2 the programs quantity of usual quality will be peer to 224th. Тhat is in one sector the signals transferred by 224 cameras can be collected. In the presence of 8 sectors the cameras total quality in network will be peer to 1792! The Total amount of the information transferred in a network reaches 7.168 Gbps!

The bottom level is made by the small networks including to 16 so-called «Points of the video surveillance». The point of a video surveillance is an aggregation of the camera, the video signal transmitter and the remote control signal receiver. Points of a video surveillance can be stationary and mobile. As each of them transmits a signal only from one camera, radio channels can take place in ranges L and S. Stationary points by means of the referred antennas contact posts of a video surveillance mainly in LOS mode. They suppose signals of the most different standards use including analog that allows to use at this level inherited (i.e. used earlier) elements of the bottom level network. Mobile points of a video surveillance are mainly systems of automobile basing. Thus the PTZ video camera, the output power amplifier of the transmitter and the antennas settle down on a car roof, and all other equipment – in its salon. Remote control of the camera can be carried out for choice or the operator at the Central Station, or the operator who is in salon of the car.

Other variant of mobile station is mobile reporting television station. In interests of public order protection and tracking safety of traffic organs the mobile point of a video surveillance can be placed by the helicopter (piloted or pilotless). In all cases of mobile application the transmitting standard DVB-T which allows to conducting transfers from a vehicle during movement is used. Besides, mobile points can work in NLOS mode (non light-off-site).

View of a video surveillance post which has the container with a thermostat. (One reception antenna UHF is conditionally shown only)

Reconciliation and reduction to a common denominator of the signals arriving from points of the video information gathering and corresponding to different standards is a problem of a video surveillance post. A post ultimate goal is transfer of a multiplex from 8-16 ТV signals according to standard DVB-S/S2 (types of modulation QPSK/8-PSK). At first signals of each of points are received separately everyone by the receiver. Analogue signals are digitized and compressed. Further transport streams DVB are formed of them. Digital signals also are processed to level of transport streams DVB. Further these transport streams are multiplexing, and the multiplex of television signals is formed of them. Then according to standard DVB-S/S2 modulation of carrier on intermediate frequency is carried out. The equipment with which help all this processing of signals is carried out takes place in a small heated premise or in the special water-proof container supplied with a thermostat. Only the transmitter (the powerful upconverter-BUC) and transmitting Ku–band antenna, and also the antennas receiving signals from points of the video surveillance are placed outside of premise or container.

Such architecture provides the maximum flexibility, multi-variant approach and that the most important thing, scalability of a network.

The block–diagram of Video Surveillance Post. System of cameras control

The transmitters of a video information gathering points and PTZ video cameras parameters control made remote. The remote control of transmitter is carried out by means of remote control receiver into which structure enter LNA, the remodulator, the decoder and the decoder of control commands, and key parameters of options are reflected by the indicator located on the forward panel.

The majority of video cameras which are supposed to be used within the limits of the given system are automated. They can be remote directed to surveillance object on two coordinates and have zoom lenses. The remote control transmitter carries out frequency modulation of carrier by low-speed (up to 19.2 Kbps) digital signal. At the output power of the transmitter peer 1W and use pin omni-directional antennas necessary range of a signal transmission from the central station to surveillance point even is provided at NLOS mode. In a figure one camera is conditionally shown only. From one control panel it is possible to control operation more than 200 cameras.

The chairman of the PrJSC “ROKS” board Ksenzenko P. Y.

Ukrainian Patent № 54644, 25.11.2010

P. Ksenzenko, M. Boichenko, P. Himich,

“ROKS”-company

The invention concerns a multichannel digital television and audio broadcastings systems, including – to networks of a multichannel single frequency synchronous broadcasting (multichannel SFN).

The device which includes the frequency downconverter which serves for conversion downwards on frequency, at least, the first and second radio-frequency signals for obtaining, at least, the first and second lower frequency signals and the multiplexer which serves for multiplexing, at least, the first and second lower frequency signals for the purpose of a multiplexed on frequency signal reception [1] is known.

The invention is based on the statement that noise sources can bring the correlated noise which is added to the received parallel branches signals (for example if the invention is realised in the equipment on the basis of silicon in parallel receive branches, and in receive branches for signal processing the general frequencies synthesizers or when at the silicon equipment somewhere there are general sources of noise) are used. The correlated noise can lower data transmission rate or information capacity of the data link in the receiver. The invention is based on the statement that at frequency multiplexing, at least, the first and second radio-frequency signals in the general multiplexed signal noise sources cannot bring the correlated noise in the received signals as at their consecutive multiplexing of the low frequency first and second signals frequencies band are divided further. Thus, each of separate signals united in a multiplexed signal is affected various not correlated spectrum components of noise sources. As a result of it the noise level in the received signal decreases.

The lack of the specified device consists that the receiver and transmitter architecture is intended for systems with many transmit and many receive antennas (MIMO) and has for an object decrease in noise level in the receiver at the frequency multiplexing expense of the several received signals on intermediate frequency. Multiplexing in this device is made on an intermediate frequency that is at physical level, instead of in the propagation environment. In the given system frequency multiplexing realises auxiliary function in system MIMO – at the expense of a noise level reduction at receiving it allows to system throughput increase and its information capacity increase. MIMO on itself assumes spatial multiplexing and is effective only in the propagation conditions to which presence a great number of the strong reflected signals (the Rayleigh mode) is peculiar, and is ineffective at the modes close to “line–of-sight” mode.

Multiplexing on IF lack is necessity for power amplifiers to gain multiplexed (that is multifrequency) signals that demands from them the raised linearity. The requirement of the raised linearity causes low amplifiers efficiency. In MIMO transmitters gain only the signals and radiate them through the antennas, but each of them will gain a multifrequency signal, and therefore requirements to linearity of its amplitude characteristic increase.

In transmit channels the signals received by means of a method orthogonal frequency multiplexing – OFDM, or its version – COFDM which are formed by means of return fast Fourier transformation – IFFT can be used. These signals are created in the transmit channel and consequently the method OFDM (COFDM) is considered as modulation method, instead of by channels multiplexing methods and at merits and demerits studying of various multiplexing schemes it cannot to be taken into consideration.

The device which assumes application of not electric (mainly fiber-optic) internal connections between the baseband processor and the radio-frequency transceiver mounted on a towering platform (tower), that is with use of the known standard equipment placing principle for communication systems. Replacement an electric line of a baseband signal transmission in the coaxial cable or twisted pair form which connects processor with the radio-frequency (RF) transceiver on a fiber-optic cable promotes baseband equipment protection (the channel forming equipment) from currents which induced at lighting discharge and which translate downwards on an electric cable (in particular – on a coaxial cable). Supply voltage and communication signals transfer is usually made from the channel forming equipment to placed on tower top RF transceiver by means of one or several cables (including coaxial cables).

On these cables transfer of lighting discharges induced currents (which arise at lightning hit in the antenna) is possible, for a set of that can to be damaged both a cable, and the baseband processor together with the interface and other equipment placed with the tower basis or near to it.

According to the specified device potential risk of influences on the baseband equipment induced by lighting discharges currents which are flowing down on a coaxial cable, it is excluded by replacement of electric connections (coaxial cables) on not electric (fiber-optic cables). As a result of such replacement at lightning hit in the antenna the induced currents not translate to the baseband equipment which settles down about the tower basis. The best at such replacement are the fiber-optic cables, which interfaces with the baseband equipment and RF transceiver realized in the form of electrooptical and optoelectrical converters. Except communication signals, on fiber-optic cables the duplex management signal can be transmitted.

A supply voltage for RF transceiver moves on a tower by means of a separate electric line which should be reliably protected inclusion of corresponding protectors and due shielding [2].

The specified device lack is that in it fiber-optic cables are used for baseband signalling. It causes the modem equipment placing at tower top, increasing thereby the working in more severe conditions equipment quantity. If in system the frequency multiplexing on air method is used that is each transmit channel is transmitted by means of separate transmitter and antenna such construction will be unprofitable as at it the quantity of the equipment located at a tower top and subject influence lighting discharges and industrial disturbances considerably increases.

To the reasons, disturbing to achievement of expected technical result at use of the known device, that in it on a fiber-optic cable the baseband signal is transmitted that leads to necessity of placing at a tower top the modem equipment which is compelled to work in more severe conditions concerns, and by transmitting of channels set in multichannel system on single fiber-optic cable system stability to disturbances decreases and requirements to converter linearity increase.

Closest of devices which is used on the same appointment, as declared, the device which has usual system of transmitting antennas for base station with input terminals set, set of multiplexers – transmitters which consist bandpass filters set, the connections blocks connecting their inputs, output terminals which are connected to one of antenna system input terminals, and also transmitters set which are grouped according to filters frequencies connected to their inputs is. Transmitters multiplexers bandwidth choose so that all their bandwidths were located in the full frequencies range intended for given mobile communication system. Feature of transmitters groups is their ability automatically to retune frequencies of a multichannel radio signal according to a band. Thus, the system can operatively be switched from the channel to the channel.

In the specified device the frequency multiplexing method for transmitters in a land mobile communication system at which use probably essential reduction of transmit power level change even when frequency on which the transmitter works, quickly changes the value in the allocated frequency range is introduced. Application of such system allows minimize the general losses and nonlinear distortions even in cases of the general antenna system use for set of multichannel transmitters.

In the specified device the multiplexing system is applied to transmitters of the mobile communications land systems, using antenna systems in which antennas elements are located so that to prevent a mutual interference or to get an antenna surface with elementary vibrators set, each of which has an independent input and has such execution which allows to exclude a mutual interference; multiplexers set of the transmitters connected by means of feeders system to the general antennas system and combining signals, arriving from bandpass filters (BPF) set; the connections block connecting BPF inputs set, which output terminal is connected to one of antennas system input terminals [3]. The specified device is chosen as a prototype.

Specified devices lack is that the multiplexer in the given device, in essence, is the complicated variant of the multiplexer which is usually used for multiplexing at physical level, namely, – at level RF parts of a transmit path on a joint with antennas system. Such multiplexer consists bandpass filters set and the same quantity ferrite circulators. If the system is multichannel signal losses in the multiplexer of this kind will be big enough. The multichannel signal is radiated in an air by antennas system which consists of the elementary vibrators connected to the help of hybrid bridges. Receive and transmit signals are divided with the help of duplexer which consists from three-branch ferrite circulator and two filters. In the given system during each moment of time by means of the switchboard everyone filter output of any transmitters groups is connected to an antennas system. The duplexer, the switchboard and filters together make the multiplexer.

Multiplexing in the specified device make not in the propagation environment, and on physical (PHY) level as the multiplexer is located before an antennas system especially lacks of the resulted scheme will be obvious to base stations with the big radiated power also. Between transmitters output and an antennas system input the difficult multiplexer which incorporates set of filters, the switchboard and circulator is included, each of which brings the contribution to signal losses. Inevitable big signal losses in the multiplexer for which account the signal arrives in antenna system weakened, are the main lack of a prototype.

The task in view dares because a television and audio broadcasting network in a frequency multiplexing mode in the propagation environment are included by the multiplexer connected to transmitters outputs and antenna system input, and also N – omnidirectional antennas which are connected with N – transmitters in the powerful upconverters form connected with N – channel crossover which is connected with N – bandpass filters which in the first variant are connected to single-channel optical receivers which through a multicore fiber-optic line are connected to inputs N – optical transmitters, and the power supply is connected with N – channel crossover and N – single-channel optical receivers, and in other variant N – bandpass filters are connected to block N – transmodulators with synchronization schemes with a support on signals GPS which are connected with the low noise downconverter block (LNB) which is connected to antenna a receive RRS.

In the declared device for the losses reduction purpose and an exception of increased requirements to transmitters linearity, and also for increase the general stability of system to disturbances and reduction of its total cost in system frequency multiplexing in the propagation environment (on air) and separate channels transmitting on IF from CS to BS set on multicore fiber-optic cables or on radio relay communication lines is used.

Starting with declared, connection specified known signs and essential signs set of the declared device provides essential increase in the service zone sizes. It is reached at the expense of increase for each separate radio channel of radiated power, and also at the expense of a multichannel single frequency synchronous broadcast network construction possibility obtainment in which in the centers of mutually overlapping cells the declared devices (Base stations) take places. Accompanying useful system signs are increase the single-channel transmitter efficiency and simplification and reduction in base stations price possibility because at IF signaling on separate veins of multicore fiber-optic cables the system synchronization becomes simpler, signal losses decrease and system firmness to disturbances raises. Besides, lighting protection becomes more reliable.

The essence of the offered useful model is explained by the figures represented on: Fig.1 – the system block diagram (the Variant 1), Fig.2 – the system block diagram (the Variant 2).

The design of an equipment radio-frequency part (the Variant 1 and the Variant 2) and its elements for both variants remains without changes. In the equipment are applied: N – omnidirectional antennas (ANT1 – ANTn), N – transmitters in the powerful upconverters form (BUC1 – BUCn) 2, crossover N – channel 3 and N – bandpass filters (BPF1 – BPFn) 4. On it similarity between two variants comes to an end.

Other part of a complex works thus: (Variant 1) Separate channels signals on IF which have modulation QAM64 (DVB-C) or COFDM (DVB-T), arrive on inputs of N optical transmitters 7. Here they will be converted to an optical range and transmitted on separate veins of a fiber-optic cable 6 which connects a studio part of a complex to that its part which it is placed at tower top (in an installation site of a radio-frequency part). This part begins with single-channel optical receivers 5 which will convert optical signals back to IF signals. At the expense of signaling on a fiber-optic line all problems allied with a signal losses will be remove, and also high immunity from disturbances is reached. The distance on which the signal on fiber-optic line can be transmitted, can reach 15 Km and more.

The main differences of declared system from existing will be the following:

– Use of single-channel transmitters signals frequency multiplexing method in the propagation environment (on-air) by means of omnidirectional antennas system, – IF signaling of separate channels from a studio complex part to its part which settles down at tower top, by means of the multicore fiber-optic cable including in the design a conductor which serves for supply voltage giving from the power supply 8 on a radio-frequency part of a complex and optical receivers. Such construction allows to transmitting signals on the big distances and excludes noise and disturbances accumulation on fiber-optic line. Signaling possibility on the big distances and maintenance thus high noise immunity in the conditions of the industrial disturbances action, reached at the expense of fiber-optic cables use, allows construct on the basis of given BS a network of a single frequency synchronous broadcasting (SNF) for each of channels set, which are multiplexed in the propagation environment.

Thus signals from network CS (the Studio complex) to a part of network BS on fiber-optic cables that allows organize a single frequency synchronous broadcast network for each of channels. Besides, as delays by transfer on fiber-optic line on distances of several tens kilometers are very small and can be in advance defined, and the reflected signals are absent, synchronization of all network is reached on CS by a delay dispersion correction in each of channels. At the big sizes of a network it can give considerable economic benefit as the corrector quantity will be minimal.

BS block diagram, which is represented on Fig.2 (the Variant 2), assumes use in networks in which for any reasons lining fiber-optic cables for connection CS with BS set is impossible. In such networks instead of fiber-optic it is offered to use simplex radio relay communication lines (RRL). By group multichannel signals transfer on RRL frequency multiplexing, but reached on PHY level also is used. Signaling on RRL and a broadcasting by means of BS are made with different standards signals use (DVB-S – on RRL and DVB-T – for a broadcasting on BS), therefore for the purpose of signals conversion from one standard in another in paths of signal processing it is necessary to establish the transmodulators QPSK/COFDM block 5 (Fig.2) in which transport streams processing is provided.

For group multichannel signals transfer on RRL frequency multiplexing, but reached on PHY level also is used. Therefore synchronization in SFN should be carried out already on BS, and on CS pilot-signals are entered.

Fig.1

Fig.2

The block diagram (Fig. 2) includes the omnidirectional antenna 1, the powerful upconverter (BUC) 2, crossover N – channel 3, the channel bandpass filter (BPF) 4, the block from N – transmodulators with synchronization schemes with a support on signals GPS 5, low noise downconverter block (LNB) of receive RRS 6, and also the receive antenna of RRS 7.

The system works as follows. The multichannel group signal which for given BS is formed on CS and is transmitted by means of transmit RRS, is received by antenna receive RRS 7 and will be converted by means of the downconverter 6 to an intermediate frequency signal. Signal IF moves on a transmodulators block 5 inputs, in it separately for each of channels transition from modulation QPSK to modulation COFDM and symbols COFDM transmitting synchronization with the corresponding symbols transmitted by others BS in a network is carried out. In the channel correction block the received pilots-signals are analyzed. According to results of this analysis transfer function of a communication channel is defined and channel correction is carried out – the signal of everyone carrier is multiplied by value of the found transfer function for this carrier. In the following block it is carried out deinterleaving another (internal) interleaving and assembly – the operation opposite to decomposition of bits on symbols. As a result the sequence of bits which arrives further on the error correction block, similar to the corresponding block of the receiver of satellite digital TV turns out.

From transmodulators outputs IF signals which have passed through channel BPF, are deliver on powerful upconverters 2 (if frequency convertion is not required, and transmitting is carried out on the same frequency on which modulation in the transmodulators block, frequency converters change on power amplifiers is made). The give radio frequency signals radiate on air omnidirectional antennas 1. For the given variant basic novelty consists in use of frequency multiplexing in the propagation environment.

Referencies:

1. The USA Patent – № 7583650, Sep.1, 2009, vol.1346, №1
2. The USA Patent – 2004/0208590A1 Oct.21, 2004.
3. The USA Patent – № 4211894 Jul.8, 1980, vol. 996, №2

The applicant, general director of Company “ROKS” Ksenzenko P. J.

The invention formula

The base station supporting on-air frequency multiplexing which includes the multiplexer connected to transmitters outputs and an antennas system input, differs that N – omnidirectional antennas are connected to N – transmitters in the form of powerful upconverters which are connected with N –channel crossover which is connected with N – bandpass filters which in the first variant are connected to single-channel optical receivers which are connected by means of N – channels fiber-optic lines to inputs N – optical receivers, and in the second variant N – bandpass filters are connected to block N – transmodulators with schemes of synchronization with a support on signals GPS which are connected with the low noise downconverter block (LNB) which is connected to antenna receive RRS.

The applicant, general director of Company “ROKS” Ksenzenko P. J.

ABSTRACT

Object of invention: Base station supporting on-air frequency multiplexing.

A scope: the Useful model concerns systems multichannel digital a television and audio broadcastings, including – in networks of a multichannel single frequency synchronous broadcasting (SFN).

An essence of useful model: The base station of a network a television and audio broadcastings includes N – omnidirectional antennas which are connected with N – transmitters in the form of powerful upconverters which are connected with a N –channel crossover which is connected with N – bandpass filters which in the first variant are connected with single-channel optical receivers connected through a N –channel fiber-optic line to N – optical transmitters outputs, and the power supply is connected with a N –channel crossover and with N – single-channel optical receivers, and in the second variant N – bandpass filters are connected to block of N – transmodulators with schemes of synchronization with a support on signals GPS which are connected with the low noise downconverter block (LNB) which is connected to receive RRS antenna.

Technical result: Provides essential increase in the service zone sizes at the expense of increase for each separate radio channel radiated power, and also at the expense of a multichannel single frequency synchronous broadcast network construction possibility gaining, in the centres of mutually overlapping cells which take places declared BSs. The declared system provides increase in efficiency of single-channel transmitters and possibility of simplification and reduction in base stations price because at IF signalling on separate veins of a multicore fiber-optic cable the synchronization system becomes simpler, decrease signal losses and the system noise stability raises. Besides, lighting protection becomes more reliable

Ukrainian Patent № 54643, 25.11.2010

P. Ksenzenko, M. Boichenko, P. Himich,

“ROKS”-company

The invention concerns to a radio engineering, in particular to systems which provide television broadcasting, gathering of a video information, and data transmission within a certain geographical zone on district.

The device which represents the wireless system which is a network of cellular communication is known and uses set of channels with distribution on frequency according to a method of frequency division multiplexing (FDM). For wireless communication realization between the user’s equipment (UE) and base station (NodeB) define, at least, one parameter which depends on a frequencies band, for, at least, one set of channels FDM at the expense of processing in NodeB. Depending on a frequencies band parameters transfer from station NodeB serving a cell to station NodeB serving other cell. Depending on a frequencies band the parameter can be defined on the basis of the response to the scheduler information and/or on the basis of concerning to frequencies band measurements which are made in NodeB. The specified system has the first configuration receivers on the power, the second configuration on power and receivers of the scheduler messages which specify in a frequencies band FDM.

Frequencies band choose from the list which consists, at least, of the first and second frequencies band FDM. Terminal UE transmits a signal of the first power level in case the scheduler message will specify in first band FDM, or the second power level if will specify in any other band [1].

Lack of the presented device is that at simultaneous reception of broadcasting and information signals compensation of losses in a rain at the expense of increase in Central (Base) station CS (BS) transmitter power does not allow to reduce a dynamic range of user’s receivers to necessary level. At the expense of transmitter CS output power change it is possible to support only at constant level equivalent isotropic radiated power (EIRP) on a service zone border. If for compensation of losses in rain CS will start to increase power on an output of its transmitter, the signal level received by close located stations for which in a rain it is much less than loss, than for being on a service zone border, will increase practically by the same size, that is the dynamic range of receivers remains invariable.

Effective from the view point of a necessary dynamic range achievement on receivers CS and User’s stations (US) inputs the way of transmitters output power change according to which it adapts for each of receivers individually on the basis of a method “from a frame to a frame”, cannot be applied as the basic adjustment mechanism by simultaneous transfer of broadcasting and information signals. The increase in reply to increase in losses in a rain of CS transmitter output power allows to support at constant level EIRP on a service zone border, but does not allow to reduce a dynamic range required for user’s receivers on an input as at such increase approximately on the same size power on the receivers inputs located near to CS the US for which losses in a rain are small increase also.

Closest of the devices applied on the same appointment, as declared, UWMS which includes CS, gathering of a video information subsystem and set the US is. CS it is divided into the segments which quantity is equal to quantity of antenna system sectors. CS has communication with such external systems: station of remultiplexing, forming television broadcast signals, external in relation to CS data transmission networks and system of receivers and means of video information record and display. The subsystem of a video information gathering has two-level structure and consists of video information gathering posts and set of video information gathering points (points in which video cameras are established).

Use the USs of two types: the first type – what are intended for reception of broadcasting signals and direct data links signals, and also for data transmission to CS under the return data link, and the second type – what are intended only for broadcasting signals reception. By means of the given system such functions as can be realized:

• A multi-program television broadcasting signaling,
• An exchange in an interactive mode the Internet and its applications data with user’s stations set at use of own return channel,
• Data exchange with corporate users on allocated channels,
• Transfer on return channels, except the data, on the frequency channels and in a real time mode, multiplexes which consist of the several transport streams formed by video information gathering posts (top level of a video information gathering subsystem),
• Transfers on wire and wireless channels of television signals from several video information gathering points (stationary or mobile points of an arrangement of video cameras) on a video information gathering post (low level of a video information gathering subsystem) [2].

The specified system is chosen as a prototype.

Lack of the presented device is that rather low level of US receivers and the receivers established in each of CS sectors adaptation to the big change range of television broadcasting signals levels received by them and the signals transferred by a video information gathering subsystem is peculiar to system UWMS. Such big change of levels range is a consequence of the big distinction in distances from CS to the subscribers and video information gathering posts location, and also attenuation of signals in a rain. The big change of levels range on receivers inputs in system UWMS can be partially compensated for account AGC in DVB receivers and at the expense of antennas with various gain factors application that can appear sufficient in usual conditions. But in the conditions of heavy rains losses from which cannot be neglected for signals with the frequencies used by system UWMS, the specified ways of the received signals levels compensation (size of a dynamic range on receivers inputs) will be for certain insufficient. Other of essential lacks are great difficulties and expenses of time for system installation as each of the US and each of transmitters of video information gathering posts demands not only individual adjustment of antennas at orientation on CS on a elevation and an azimuth, but also individual selection of antennas gain factors (dish diameters). System operation as for the operator on CS there will be accessible only on information part of system work is complicating, and it will be known nothing about quality of television signals reception. At the same time, monitoring of TV transfer channels is especially important because in system work television broadcasting signals which should be transmitted with bit errors rate not big than BER = 10-8 should be priority. Such high BER the real time mode demands by transfer, both broadcasting signals, and the signals transferred by a video information gathering subsystem.

One of those reasons which obstruct with achievement of expected technical result at use of the known device, that in the heavy rains conditions the general dynamic range on USs receivers inputs, and also CS receivers at video information gathering subsystem signals receiving by them, will be too big is and cannot be provided by those means which are available in system UWMS. For acknowledgement of it we will result such calculations.

The first dynamic range component are losses in a rain. Losses of a signal at the expense of absorption in a rain substantially depend on frequency. On frequencies below 5 GHz these losses in most cases can be neglected. But on the fixed communication and broadcasting lines, working on frequencies above 20 GHz, losses in a rain become a primary factor limiting communication range. Naturally, losses in a rain depend on its intensity. In a heavy rains zone on the foreground there is a peak rain intensity which is observed throughout 0.1 % of time that corresponds to usual value of a line readiness 99.9 %. It is much more important, than the general annual norm of rains. Peak intensity strongly depends on a geographical zone. In droughty regions rain intensity can make only a few millimeters per hour. In regions with very heavy rains peak values of intensity can reach to 150 mm/hour. All calculations for communication systems can be conducted taking into account hourly average distribution of rain intensity for the worst month of year. The easing size at absorption of a radio signal by hydrometeors V in dB is defined under the formula:

V=-y*Rэф where y – attenuation factor, dB/Km, Rэф – effective length of a line, Km, along which the attenuation factor is approximately constant and equal .

The attenuation factor, for example, on frequency of 11 GHz for region with rain intensity 50 mm/hour is equal about 2 dB/Km. It means that the stock on attenuation on a line in length of 15 Km is equal in a rain approximately 30 дБ, application of broadcasting and data transmission systems which work on higher frequencies, than applied in declared system, in regions with such amount of precipitation in general is impossible.

Each of sectors CS transmitter output power level has the fixed size. This size is gets out maintenance of minimum necessary relation a signal/noise (SNR) calculation for the most remote subscriber station under the worst receive conditions. A component of a dynamic range is also signal attenuation in a rain which depends on distance between the USs and CS.

Declared system UWMS-R is a fixed communication system that is position in space of all subscriber stations rather CS is known in advance. We will admit that the CS service zone radius is equal 15 Km, and the most approach from closely spaced subscriber stations is from CS on distance of 150 m. Then the propagation lines lengths rate for the station which are on border of a service zone, and the station which are from CS on distance of only 150 m, will make 100:1.

The received signals powers relation for these stations, expressed in dB, is calculated under the formula which is recommended by the International Telecommunication Union (ITU) and looks like:

10N*log d = PT (dBm) + GT (dB) + GR (dB) – 32.44 – PR (dBm) – 20 log f (MHz). where: PT = output transmitter power (dBm);

GT = the transmitter antenna gain factor (dB);

GR = the receiver antenna gain factor (dB);

f = average working frequency of a radio channel (MHz).

Factor N named losses exponent and characterizing radio signal propagation conditions on a line, we will choose from Table 1.

Let’s choose N = 2.7. If the relation of distances equally d1/d2 = 100, then 10N*log d1/d2 = 10* 2.7*log 100 = 54 дБ.

Thus, the signals dynamic range on USs receivers inputs who is caused by distinction in distances to CS, will be equal 54 dB (a mode almost to “line-of-sight”, but taking into account city propagation conditions). This component of a dynamic range is a constant and practically does not depend on time. If to consider losses in a rain which are a variable dynamic range component in power levels of received USs and CS signals on USs receivers and CS receivers of video information gathering subsystem inputs will reach possible difference 84 dB.

The method which most often use for increase in a dynamic range at a receiver input, is use of automatic gain control (AGC) in the receiver. As receivers in a broadcasting part the US and in a CS video information gathering subsystem apply standard tuners (set-top box) standard DVB. The signal admissible levels range on DBS tuner input at work in a land broadcasting systems makes from – 50 dBm to – 20 dBm that corresponds to AGC depth nearby 30 dB. Some reduction of control depth in AGC scheme rather 40 dB which correspond to broadcast satellite channels receiving, speaks higher own noise level of land broadcasting systems receivers concerning noise in DBS systems because of what the control range bottom level raises approximately on 10 dB, and the control range decreases to 30 dB. However it is obviously not enough this range for all range of receiver input signal level change full compensation which as it has already been told, can reach 84 dB. In declared system UWMS-R for partial compensation of such big received signals level difference which is peculiar both to US receivers, and to intakes which belong to CS video information gathering subsystem receivers, the way of corresponding choice gain factors (diameter of dishes) user’s stations parabolic antennas and respective choice of gain factors US receive and transmit MW converters and receive-transmit MW heads transmitting parts converters of a video information gathering posts can be applied.

Such control is carried out in US receive-transmit MW heads and can be realized at the expense of additional AGC loop which covers high-frequency receivers stages. AGC voltage simultaneously can be used and for control on the same size of receive-transmit MW heads transmit parts gain factors that is possible thanks to receive and transmit channels similarity. Such way is simple enough, but has essential lacks. Receive-transmit MW heads receive part receives not only broadcast signals, but also and a direct information channel (downlink) signal. At gain factor adjustment the priority should be given television broadcasting signals as they demand transfer to a real time mode, and admissible at their reception error bit rate on two order more low, than necessary for information channel correct reception (10-8 against 10-6). If all control in broadcasting channels to concentrate on the US operatively to supervise reception quality by it of broadcasting signals, being on CS, it will be impossible. At the same time, one of the important MAC components in the central station (WMTS) modem is the quality management program (QoS) which allows to operating work of data transmission network flexibly. The similar system is necessary and for broadcasting channels.

One of the lacks inherent in gain adjustment systems which are completely concentrated inside the USs, the big complexity and duration of all system installation process is. It will be necessary to establish threshold values for AGC in each of receive-transmit MW heads individually taking into account a distance to CS that at a considerable quantity of subscribers a lot of time will demand. For lack of all system monitoring work on CS it is impossible to react operatively to receiving conditions degradation for separate US and to force with its work mode. Therefore gaining management in sizes of factors, both receivers, and transmitters it should be spent distantly and automatically from CS equipment room. At use AGC in the receiver (DVB tuner) and remote adjustment mode of receive-transmit MW heads receiving and transmitting parts the general levels difference compensation will make 64 дБ. To full compensation does not suffice still, at least, 20 дБ. The further compensation can be carried out at the expense a service zone division which is concentrated in sector with a beam corner 360 deg./N, at least, on two parts. The first of them is concentrated in approached to CS to a zone, where signal level high enough. Here it is possible to take advantage of the antennas having on 20 дБ smaller gain factor (smaller dish diameter). On the contrary, in a remote part of a zone we will take use of antennas with the maximum gain factor. Now we will obtain a necessary general dynamic range 84 dB.

Range of signals levels change received the US which mirrors a radiated by CS transmitter signal level dependence in US receivers inputs only from distance to CS at power level on CS transmitter output corresponding to power which is necessary for obtaining in the most remote user’s receiver minimum SNR plus loss in a rain at the maximum removal from CS. Signal level dependence on losses in a rain which, being expressed in dB, are proportional to distance to CS, looks like a straight line if received power has a logarithmic scale. By transfer of television signals the direct broadcast channel and the return channel of the video information gathering system are similar, as in they use identical modulation type and the same frequencies band. For dynamic range reduction the signals received by downconverters and receivers (DVB tuners) should be changed to the same size, as their receive converters gain factors. That such system successfully worked, it is necessary to enter into it the feedback channel on a received US signal level. As the information transfer physical channel about a signal received the US level it is the most convenient to use the return data link (upstream) own information part of system, and for management in gain factors of receive-transmit MW heads US receive and transmit converters and video information gathering posts receive-transmit blocks – the direct data link (downstream). Essential changes to the block diagram as separate sector CS, and in video information gathering post scheme for this purpose was necessary to make.

The task in view dares because system UWMS-R includes the central station, a video information gathering system and user’s stations, thus the central station has segments, each of which has the sector aerial which on an input-output is connected to an diplexer output which on an input is connected to the upconverter, and on an output – with the downconverter which is connected by the output to the downconverters block which N – outputs is connected to the modem (WMTS), and an output is connected to video information gathering system receivers, and the output connects to the main computer (server) which has an interface to external distributive networks, and an output the modem is connected to the upconverter input, which the output is connected to one of combiner inputs which other input is connected to one of N –channel power divider inputs, and an output is connected to the upconverter, which is connected by an output to diplexer input, the multichannel power divider by N –outputs is connected with N – segments combiners, and the input connects to the multichannel combiner which N – inputs is connected with N – modulators of remultiplexing station, and the central station modem an input – by an output is connected to the switchboard which one of inputs–outputs is connected to the monitoring and management block, and by other input –output is connected to a digital platform which by N – inputs-outputs is connected to N – segments switchboards, and the user’s station of the first type has the antenna, the receive-transmit MW head, the transceiver, tuner DVB and the user’s modem (CPE), on an input receive-transmit MW heads the polarization selector which on an input-output is connected to the antenna which is connected by one of outputs to the filter which is connected by the output to the low noise amplifier input which on an output is connected to other filter which on an output is connected to mixer input, and other mixer input is connected to one of local oscillator outputs, and by an output is connected to an input of the first amplifier with gain control, the amplifier output is connected to the transceiver which is connected to a mixer input of receive-transmit MW heads transmitting part, and other mixer input is connected to other local oscillator output, a mixer output is connected to an input of the filter which is connected by the output to an input of the second amplifier with gain control, which input and input of the first amplifier with gain control is connected to the transceiver, the output of the second amplifier with gain control is connected to the power amplifier input which is connected by the output to the polarization selector input, and receive-transmit MW head is connected with the transceiver duplexer, one of duplexer exits is connected to the downconverter input which is connected by the output to the multiplexer input which is connected by the input-output to an input-output of the user’s modem, and the output connects to the upconverter input which is connected by the output to receive-transmit MW heads transmitting part, and other duplexer output is connected to directional coupler input which is connected by the output to the detector which is connected by an output to the modem input which is connected by the input-output to the switchboard, and the switchboard an input-output connected to the user’s modem, and by other input-output is connected to an external data transmission network, and by an output is connected to operating input of receive-transmit MW heads, and the output directional coupler is connected to tuner DVB input, and the receive-transmit block consists of the antenna, the receive-transmit MW head, the transceiver and the user’s modem, a receive-transmit MW head which has the structure coinciding with structure receive-transmit MW head of user’s station, an output of the receiving part is connected with the transceiver duplexer input which is connected by an output to the downconverter, which is connected to one of multiplexer inputs which is connected by an input-output to the user’s modem, and by an output is connected to a combiner input which is connected by an output to an input of a receive-transmit MW heads transmitting part, and by other input is connected to the video information gathering post modulator block output, and the transceiver duplexer output is connected to the detector which is connected by an output to encoder/decoder input which is connected by an output-input to an input-output of the user’s modem, and by other output is connected to receive-transmit MW head control input, and the second type user’s station MW downconverter has auxiliary AGC loop.

On the stated basis, the resulted known signs connection and a declared product essential signs set is provided substantial dynamic range growth by the US receiver inputs, signal radiated by receive-transmit MW blocks transmitters of a video information gathering posts levels difference reduction and, thus, a necessary separate CS segments receivers dynamic range reduction. It is necessary to notice that regardless of the fact that control in system is carried out on the basis of power measurement in broadcasting channels, this control is very useful and by direct and return channels transfer of own wireless data transmission network because promotes a control range reduction in the user’s modem. That is especially important at work in a time division multiple access mode (TDMA). The declared system keeps working power during heavy rains, but it can be used and in usual conditions as she allows to lower expenses for system installation and to lower working costs.

Essence offered invention it is explained by the drawings represented on: Fig.1 – system UWMS-R block diagram; Fig.2 – user’s station USn; Fig.3 – receive-transmit block of a video information gathering system.

UWMS-R which represents system MVDDS united with a video information gathering subsystem, consists of following basic elements: the central station 1, a video information gathering subsystem 2 and the USs set 3. CS 1 consists of the segments 4 which quantity N depends on antenna system sectors quantity (from 1 to 8 sectors). Each of segments 4 consists of the sector antenna 5 which on an output-input is connected to a duplexer 6 output-input which on an input is connected to the upconverter 7, and on an output – with the downconverter 8. The downconverter 8 is connected by output to the downconverters block 9 which N – outputs is connected to CS modem (WMTS) 10, and by an output is connected to video information gathering subsystem receivers. The modem 10 is connected by input-output to the switchboard 13 which is connected by one of inputs-outputs to the monitoring and management block 14, by other input-output is connected to one of inputs-outputs of a digital platform 15, and by an output is connected to the upconverter 11 input. The upconverter 11 is connected by output to one of N –channel power divider 16 outputs, and by an output is connected to the upconverter 7 which is connected by an output to duplexer 6 input. The digital platform 15 by N – inputs-outputs is connected to the CS 12 N – segments 4 switchboard 12, and by an output is connected to the main CS computer (server) which has an interface to external distributive networks. The multichannel power divider 16 by N – outputs is connected with N – segments 4 combiner 12, and by an input is connected to the multichannel combiner 17 which N – inputs is connected with N – remultiplexing station modulators.

The video information gathering subsystem 2 includes a video information gathering post 18 which is connected by radio – or the cable communication line with stationary 19 or only on a radio line to mobile video information gathering points 20, and on a radio channel is connected with CS 1 by means of the receive-transmit block 21.

All operating mode management of data transmission network is assigned to CS modems 10 which quantity equals to segments 4 quantity. Separate modems 10 traffics unite by CS digital platform 15, and the incorporated traffic arrives on the computer (a main system computer – the server) which provides interaction with external data transmission networks.

UWMS-R CS scheme differs from prototype UWMS that are entered into each of its segments structure two new elements – switchboards 13 and monitoring and management blocks 14. The switchboard 13 is intended for allocation from the general data flow of that data which concern an auxiliary data transmission network of USn receive-transmit MW heads and video information gathering posts receiving and transmitting parts gain factors control paths and the control over broadcast signals quality received by them.

In the central station monitoring and management block all management and control function that allows the operator to supervise a current network condition is concentrated. Management in gain factors user’s receive-transmit MW heads receiving and transmitting converters and video information gathering posts receive-transmit blocks is carried out in an automatic mode by means of the special program which is placed in the CS monitoring and management block.

On Fig.2 and Fig.3 the first type US receive-transmit blocks USn and video information gathering posts receive-transmit blocks the block diagrams are represented.

The first type User’s station USn (Fig. 2) consists of the antenna 1, receive-transmit MW head 2, the transceiver 3, the tuner 4 and the user’s modem (CPE) 5. On receive-transmit MW head 2 input the polarization selector 6 which on an input-output is connected to the antenna 1 is placed, by an output is connected to the filter 7 which is connected by the output to the low noise amplifier 8 input which on an output is connected to one more filter 9 which on an output is connected to mixer 10 input. The mixer 10 is connected by other input to one of local oscillator 11 outputs, and by an output is connected to an input of the first amplifier with gain control 12. From an output of the amplifier 12 signal on a coaxial cable arrives on receive-transmit MW head 2 transmitting part mixer input, and other mixer 10 input is connected to one more local oscillator 11 output. The mixer 13 output is connected to the filter 14 input which is connected by the output to an input of the second amplifier with gain control 15 on which input and on an input of the first amplifier with gain control 12 from the transceiver the management in gain factors signal is given. The second amplifier with gain control output is connected to the power amplifier 16 input which is connected by the output to the polarization selector 6 input. The signal from receive-transmit head 2 receiving part arrives on transceiver 3 duplexer 17.

Fig.1

One of duplexer 17 outputs is connected to the downconverter 18 input which is connected by the output to the multiplexer 19 input. The multiplexer 19 is connected by input-output to the user’s modem 5 input-output, and by an output is connected to upconverter 20 input which is connected by the output to receive-transmit MW head 2 transmitting part. The user’s modem 5 is connected by other input-output to the switchboard 21 input-output which is connected by other input-output to modem 22 input-output which is connected by an output to receive-transmit MW head 2 both amplifiers with gain control 12 and 15 control inputs. One of duplexer 17 outputs is connected to the downconverter 18 input which is connected by the output to multiplexer 19 input. The multiplexer 19 is connected by input-output to the user’s modem 5 input-output, and by an output is connected to the upconverter 20 input which is connected by the output to a receive-transmit MW head 2 transmitting part. Other duplexer 17 output is connected to directional coupler 23 input which is connected by the output to the detector 24 input which is connected by the output to encoder/decoder 22 input. Directional coupler 23 by it output is connected to a tuner 4 input from which the signal goes on the subscriber television receiver. The switchboard 21 has the port input of the peripheral user’s device with which help it is connected to the user’s computer or a data transmission network.

The first type user’s station USn has the switchboard 21, the encoder/decoder 22, the detector 24 and directional coupler 23. In directional coupler 23 broadcasting part of the signal received and converted to a signal of intermediate frequency (IF) in receive-transmit MW head 2, branches off in the passing power detector 24. The signal from the detector 24 arrives in the modem encoder/decoder in which it is digitized. The encoder/decoder 22 forms the data for transfer on a management and monitoring network for their inclusion in the return data link through the user’s modem 5, and also will selects and decode the data received from the user’s modem 5 under direct data link. On the basis of the management commands received from CS under the direct data link, the management signal intended for gain factor control of both receive-transmit MW head 2 amplifiers with gain control 12 and 15 is formed.

The receive-transmit block of a video information gathering subsystem (Figs. 3) consists of such elements: the receive-transmit MW head 2 antenna 1, the transceiver 3 and the user’s modem (CPE) 5. Receive-transmit MW head 2 has no differences from applied in structure USn. The transceiver 3 has following differences (elements of one appointment are numbered equally) concerning the same block USn: it is excluded directional coupler 23, the tuner 4 is excluded, added combiner 25. In use of the tuner 4 as a part of the equipment of video information gathering unattended post there is no necessity. Also there is no necessity in directional coupler 23 as all broadcasting signal goes to the detector 24.

As there is no necessity for the peripheral user’s equipment connection, there is no switchboard 21. The user’s modem 5 is used only for management and control signals reception and signaling. After reduction to one kind of all signals arriving on a post, their gathering, multiplexing of the received transport streams in a uniform transport stream and modulations by this stream carrier on intermediate frequency the modulated signal moves on combiner 25. In it this signal unites with a return information channel and goes on receive-transmit MW head 2 transmitting part. Application instead of the video information gathering channel transmitter the receive-transmit block allows to carry out control with CS under the direct data link a video information gathering post receive-transmit block transmit part gain factor and level of its output power that will allow to reduce at signals receiving from several video information gathering posts levels difference on receive CS converters inputs.

In UWMS-R also are applied the second type US (US1) which have no return data link and consequently are not subject to the control and management from CS. By this type US input in their receive converters is applied to a necessary dynamic range maintenance an additional loop of automatic gain control (AGC) which supplements the tuner AGC.

The declared device works as follows. Television broadcast signals are formed by remultiplexing station (on Fig. 1 it is not represented). The remultiplexing station usually represents a teleport which receives signals of satellite, cable, land TV, and also signals from local studio. On CS these signals are properly processed. This processing includes decoding of those signals which are coded by conditional access systems (descrambling), transport streams remultiplexing for the purpose of television programs new packages formation and scrambling these streams by own address coding system. After performance of the specified operations which are necessary for scrambled DVB streams formation, the received data flows are sent on modulators on which outputs are generated carrier, modulated by multi-program TV signals.

The modulated carriers unite in a multi-frequency group signal by means of CS multichannel combiner 17. Further a group signal power shares on N – parts (by quantity of system segments) by means of a power divider 16. On power divider 16 output obtain N – group signal copies, each of which goes on combiner 12 one of CS segments 4. After summation with the direct data link signal this signal will be converted and amplifies by the upconverter 7, then arrives on duplexer 6 input and, having passed it, is radiated by the sector antennas 5 in the form of a beam in width 360 grad./N (where N – quantity of antenna system sectors).

The downstream is formed by a transmitting part of the CS modem 10 (WMTS). In it DVB data packages with time division multiplex (method TDM), modulate preliminary selected carrier, forming the direct data link. Further this signal will be converted by the upconverter to a necessary frequencies range, amplifies and combined with the combiner 12 help with broadcast signals, forming a full group signal of the direct channel. Further it will be converted and amplifies by the upconverter 7 and, having passed through duplexer 6, is radiated by the sector antenna 5 in the form of a beam in width 360 deg. /N (where N – quantity of antenna system sectors). The signal is received by the US of first type USn 3 and video information gathering post receive-transmit blocks.

Fig.2

Fig.3

The upstream signals are transferred by USn type station and transmitting parts of video information gathering posts receive-transmit blocks in a corresponding CS sector antenna direction. Frequency and time multiplexing method (method FDMA/TDMA) is thus used. At these multiplexing method use some USn or video information gathering posts receive-transmit blocks quantity works on single frequency and transfers messages in the packages form at the CS modem 10 command. These commands are built in downstream structure in the special channel (control path) form. Such way reaches USn type stations and video information gathering posts receive-transmit blocks collision-less work with which help the information transfer on CS is carried out by them downstream data packages transfer. By the same principle also others USs work which similar USn are working on other frequencies, and also those from them which belong to CS 4 segments with numbers 2 … N.

The video information gathering system has two-level structure. Such construction necessity is caused by that the signals transferred stationary 19 or mobile 20 video information gathering points, can correspond to different standards, for example, DBS – for analogue points and DVB-T – for digital. Besides, for signals of the first level it is heavy to obtain sufficient range by transfer which would allow to transmit directly a signal on CS, because of video information gathering points transmitters (especially mobile) limited power, low placement level of transmitting antennas, and also difficult radio-waves propagation conditions (absence of “line-off-sight” mode, presence of reflected signals considerable quantity etc.). Inclusion in system structure some quantity of video information gathering posts which settle down so that for them the “line-off-sight” mode with CS was provided, allows to solving this problem. Receivers which are a part of video information gathering posts receive-transmit blocks (Figs. 1), accept and process the different signals arriving from video information gathering points, and will convert them to one kind (a kind of standard DVB transport streams TS). Further these TS are multiplexed in the uniform data stream which modulates carrier on intermediate frequency. Then this signal arrives on the transceiver and receive-transmit block 21 receive-transmit MW head in which will be upconverted on frequency and amplify for the further transfer on a radio channel in direction to CS.

On each CS segment 4 signals from USn and video information gathering posts18 which are located in CS antenna sector arrive. Having passed duplexer 6, the received signals arrive on low noise downconverter 8 in which they amplify and will be converted to intermediate frequency signals. Intermediate frequency signals arrive on a multi-channel power divider of the converter 9. This power divider has outputs quantity which is equal to quantity of the CS modem 10 inputs, plus one more output, from which one of received signal copies goes on video information gathering subsystem receivers (on Fig. 1 they are not represented). As these receivers usual DVB tuners can be used.

The network management system (NMS) is concentrated in the central station DOCSIS modem WMTS. It supervises UWMS-R serviceability and parameters by means of the monitoring and management system. Options NMS include the control of network operating modes, administration, and networks attendance and user charge acquisition from users of a network.

The sizes of service zone usually depend on the radio-frequency equipment system gain, also – gain factors of transmit and receive antennas, The region in which system UWMS is placed meteorological characteristics, and also the real signal/noise rate which is reached in system. In general the radius of service zone should be more than 10 Km.

Though spectrum UWMS-R is wide enough in comparison with frequencies bands which are caused for a point-point (PTP) and a point-multipoint (PTM) line types on lower frequencies, in declared system, except frequency and time division, is used as well spatial division of the signals arriving from the USs and video information gathering posts receive-transmit blocks transmitters, for the purpose of increase in their quantity and information capacity of a network.

At increase in CS sectors number the cost because transmitters and receivers should repeat in each of sectors increases also. However sector construction use advantage is that antennas with higher orientation degree which occurs at replacement omnidirectional antennas on sector antennas system, reduces appearance possibility of the effects associated with a multibeam propagation mode, and thereof, reduces an intersymbol interference (ISI). But decided advantage of antenna system sector construction is substantial data transmission network subscriber quantity growth and video information gathering posts quantity growth at the expense of their distribution in space and possibility of a frequencies reuse.

The information UWMS-R part works thus. Transport stream frames contain set distributed in time slots which can be divided on starting slot and arbitrary access slots. To simplify processing process in users modem CPE (decoding), it is necessary, that the passed slots relative quantity in a frame was no more than 7 %. At data transmission rate in a downlink direction 41 Mbit/s, it corresponds to 50 ATM cells or 14 MPEG-2 TS packages in a frame in 6 msec. Everyone CPE then can accept approximately to 3.5 Mbit/s. CS it is capable to transfer some channels simultaneously, however CPE can accept only one channel. It can be switched to different frequencies, but such switching can demand time interval equal to several time slots.

The frames structure is co-ordinate with a transport stream with the image and sound compression standard MPEG-2 (MPEG-2 Transport Stream). MPEG2 – TS MUX package contains 188 byte into which enter one byte of the synchronization, three heading bytes which contain the service information, the information about scrambling and management, and the following 184 MPEG-2 bytes or the additional data. Packages are scrambled with use of pseudo-random binary sequence (PRBS) with the period in 1503 bytes that corresponds to 8 packages. Synchronization bytes are not scrambled. The first synchronization byte is supplemented. According to standard DOCSIS channel coding supposes 5 composed: scrambling, interleaving, block coding Reed – Solomon, convolution coding and, at last, mapping. The downstream uses the norms corresponding to DVB standards for satellite or land services in 11 GHz and 12 GHz ranges. The system is optimized concerning access mode TDM on one carrier, but allows to apply and the scheme of multi-frequency access FDM. As typical rate of data transmission the rate multiple 8 Kbit/s defined. The frame structure is equivalent to specification DAVIC and contains 188 byte.

The access scheme in the upstream is time division multiple access -TDMA. Frame length the same, as for the downstream, that is between 3 msec and 6 msec. CPE regulates the package transfer time moment choice in an uplink direction before coincidence to slot borders in an upstream frame on CS at the set admission on time. Its accuracy is defined by a difference in a propagation delay that is in service zone radius. The network management system distributes set of adjacent time slots so that to generate longer slots the network access, interfering occurrence of collisions by TDMA package transfer which can accompany CPE access to a network. Synchronization is reached thanks to that CPE adapts the slot transfer moment in reply to a feedback by synchronization error until while this error does not become smaller, than one symbol duration in an upstream (the guard interval in a package has the duration equal to 4 symbols). CS generates periodic inquiries about synchronization error for achievement of necessary accuracy. The upstream data package contains 68 byte. The upstream frame contains F slots where number F depends on data transmission rate in an upstream. These F slots are divided on polling slots, arbitrary access slots, and reserve time slots. The each type slots quantity parity is dynamic.

Shortened code Reed – Solomon RS (204,188) is chosen as a block code for an uplink. At input bit error rate (BER) which matters close to 7 х 10 – 4 or less and at unlimited bytes interleaving, the decoder should carry out QEF (quasi error free) output at which BER makes from 10 – 10 to 10 – 11. Convolution interleaver is same most, as well as applied in a downstream under specification DAVIC (T=12, M=17), and also is the block coder. The block decoder should work at input error rate (BER) which is equivalent to “the rigid decision”, which is between 10-4 and 10-2, and should provide BER nearby 2 х 10 – 4 or less.

The roll–off factor for the filter with the type characteristic “a root square of raised cosine” (RSRC) is equal 0.35 that differs from specification DAVIC in which it is applied 0.2 or 0.35 a little. At use of digital filter FIR it is possible to carry out nonlinearity alignment (equalization) in the channel. This filter is not standardizing, therefore it will depend on concrete transfer channel parameters. The modulation scheme is usual Gray-coded QPSK.

The modem of central station DOCSIS – WMTS allows to operate the power given by user’s modems, and at the expense of it carries out adaptive suppression of ingress noise in the receiver in real time. Measurement and the analysis of the signal/noise rate in WMTS receiver is for this purpose carried out. On the basis of this analysis special commands for transmitting parts of user’s modems control are developed. Further the signal which has arrived in receiver WMTS, is processed in an equalizer that allows to increase throughput of modems DOCSIS at the granting expense practically in all cases of their work possibility in a mode 16QAM instead of QPSK. The equalizer corrects a signal at influence on it frequency fading, amplitude distortions, and also non-uniformity of a group delay. If all the same noise cannot be suppressed (for example, at very big level of ingress noise or a strong interference) WMTS can prevent consequences of noise influence at the expense of modulation type change or transition in a frequency-hopping mode (mode CDMA). For all working as a network part DOCSIS modems parameters improvement, WMTS use the additional receiver which joins in parallel the several receivers intended only for a subscriber’s network service. This receiver gives to operators possibility of an operational administration in any of uplink ports parameters, without forcing thus with their work on servicing. For this purpose the additional receiver joins to in parallel chosen receiver so that the operator could measure the traffic and signal parameters in real time for any of functioning ports. Simultaneously this receiver can have access to the network information and the full list of the user’s modems working on any of receivers, subject to monitoring. Thus, while any of receiver ports works at a total load, the additional receiver can increase access to other return channels by tests reception for each of uplink channels and their loading estimation. The auxiliary data transmission network for monitoring and management in active receive-transmit MW heads upconverters and downconverters gain factors can be constructed as usual IP network which uses own wireless data transmission network of UWMS-R as transfer media. On return information UWMS-R channels (upstream) the data intended for levels monitoring of broadcasting signals received the US is transmitted. This data is entered into the return channel by means of the switchboard 21 (Фиг.2). On CS the monitoring data arriving from all active USs, on WMTS 10 output (Fig.1) by means of the switchboard 13 separates from the given clients and goes to the block of monitoring and management 14. Here on the basis of the received data on certain algorithm management commands for each of the US which by means of the switchboard 13 are entered already into the direct data link are developed and transferred on a radio channel simultaneously to all the USs which are in given sector. To reduce quantity of the information intended for the direct channel transfer, the information on receive-transmit MW heads converters gain factors change is transferred only. On each of user’s modems (CPE) 5 output all these signals are present and arrive on the switchboard 21 (Fig. 2) with which help the data which concern only control systems separate. In the encoder/decoder 22 the management commands concern to given US are decoded and the given US receive-transmit MW heads up and down converter or the video information gathering posts receive-transmit blocks gain factors control signals will be generated.

Referencies:

1. US Patent 2008/0247375A1, pub. 2008.10.09
2. Patent of Ukraine № 36562, pub. 27.10.2008, bul. № 20.

The applicant, general director of Company “ROKS” Ksenzenko P. J.

The invention formula

1. UWMS-R that assigns for working in heavy rain regions which includes the central station, a video information gathering subsystem and user’s stations, thus the central station has segments, each of which has the sector antenna which on an input-output is connected to a duplexer output-input which on an input is connected to the upconverter, and on an output – with the downconverter which is connected by the output to the downconverters block which N – outputs is connected to the modem (WMTS), and the output connects to video information gathering subsystem receivers, and an output the modem is connected to the upconverter input which is connected by the output to one of combiner inputs which is connected by other input to one of N-channel power divider outputs, and by an output is connected to the upconverter which is connected by an output to a duplexer input, the multichannel power divider by N – outputs is connected with N – segments combiners, and by an input is connected to the multichannel combiner which N – inputs is connected with N – remultiplexing station modulators, differs that the central station modem is connected by an input-output to the switchboard which is connected by one of inputs-outputs to the monitoring and management block, and by other input-output it is connected to a digital platform which by the N – inputs-outputs is connected to N – segments switchboards, and the user’s station of the first type has the antenna, receive-transmit MW head, the transceiver, DVB-S tuner and the user’s modem (CPE), on a receive-transmit MW head input the polarisation selector which on an input-output is connected to the antenna which is connected by one of inputs to the filter which is connected by the output to a low noise amplifier input which on an output is connected to other filter which on an output is connected to a mixer input, and other mixer input is connected to one of local oscillator outputs, and an output is connected to an input of the first amplifier with gain control is established, the amplifier output is connected to the transceiver, which is connected to a receive-transmit MW head transmitting part mixer input, and other mixer input is connected to other local oscillator output, the mixer output is connected to a filter input which is connected by the output to the second amplifier with the gain control input which input and an input of the first amplifier with gain control are connected to the transceiver, the second amplifier with gain control output is connected to the power amplifier input which is connected by the output to a polarisation selector input, and receive-transmit MW head is connected with the transceiver duplexer, one of duplexer outputs is connected to the downconverter input which is connected by the output to a multiplexer input which is connected by the input-output to an user’s modem input-output, and the output connects to the upconverter input which is connected by the output to a receive-transmit MW head transmitting part, and other duplexer output is connected to a directional coupler input which is connected by the output to the detector, which is connected by an output to the encoder/decoder input which is connected by the input-output to the switchboard, and the switchboard by an input-output is connected to the user’s modem, and by other input-exit connected to an external data transmission network, and encoder/decoder by an output is connected to receive-transmit MW head control input, and the directional coupler output is connected to DVB tuner input, and the receive-transmit block consists of the antenna, receive-transmit MW head, the transceiver and the user’s modem, receive-transmit MW head which has the structure similar to structure of user’s station receive-transmit MW head, by the receiving part output it is connected to the transceiver duplexer input which is connected by an output to the downconverter which is connected to one of multiplexer inputs which is connected by an output-input to the user’s modem input-output, and by an output it is connected to an combiner input which is connected by an output to a receive-transmit MW head transmitting part, and by other input it is connected to the modulator block output of a video information gathering post, and the transceiver duplexer output is connected to the detector which is connected by an output to the encoder/decoder input which is connected by an output-input to an input-output of the user’s modem, and an output the encoder/decoder connected to receive-transmit MW head control input.

2. UWMS-R that assigns for working in heavy rain regions, under item 2 which differs that second type user’s station MW downconverter has auxiliary AGC loop.

The applicant, general director of Company “ROKS” Ksenzenko P. J.

ABSTRACT

Object of invention: UWMS-R that assigns for working in heavy rain regions.

A scope: the useful model concerns radio engineering, in particular to systems which provide television broadcasting, a video information gathering and data transmission within a certain geographical zone on district.

An essence of invention: The central station modem is connected by an input-output to the switchboard which is connected by one of inputs to the monitoring and management block, and by other input-output is connected to a digital platform which by the N – inputs-outputs is connected to N-segments switchboards, and the first type user’s station has the antenna, receive-transmit MW head, the transceiver, DVB tuner and the user’s modem (CPE), on an input-output of the receive-transmit MW head the polarization selector is placed which on an input-output is connected to the antenna and by one of outputs is connected to the filter which is connected by the output to a low noise amplifier input which on an output is connected to other filter which on an output is connected to a mixer input, and other mixer input the is connected to one of local oscillator outputs, and an output is connected to an input of the first amplifier with gain control, the amplifier output is connected to the transceiver, which is connected to a receive-transmit MW head transmitting part mixer input, and other mixer input is connected to other local oscillator input, the mixer output is connected to a filter input which is connected by the output to an input of the second amplifier with gain control which input and an input of the first amplifier with gain control are connected to the transceiver, the output of the second amplifier with gain control is connected to the power amplifier input which is connected by the output to the polarization selector input, and receive-transmit MW head is connected with transceiver duplexer, one of duplexer outputs is connected to the downconverter input which is connected by the output to the multiplexer input which is connected by the input-output to the user’s modem output-input, and by an output is connected to the upconverter input which is connected by the output to a receive-transmit MW head transmitting part, and other duplexer output is connected to an directional coupler input which is connected by the output to the detector which is connected by an output to encoder/decoder input which is connected by the input-output to the switchboard, and the switchboard by an input-output is connected to the user’s modem, and other user’s modem input-output is connected to an external data transmission network, and an output connected to receive-transmit MW head control input, and the directional coupler output is connected to DVB tuner input, and the receive-transmit block consists of the antenna, receive-transmit MW head, the transceiver and the user’s modem, receive-transmit MW head having structure which coincides with user’s station receive-transmit MW head structure, by the receiving part output is connected to the transceiver duplexer input which is connected by an output to the downconverter which is connected to one of multiplexer inputs which is connected by an input-output to the user’s modem, and by an output it is connected to an combiner input which is connected by an output receive-transmit MW head transmitting part input, and by other input it is connected to the modulator block output of a video information gathering post, and the transceiver duplexer output is connected to the detector, which is connected by an output to a encoder/decoder input, which is connected by an output-input to an user’s modem input-output, and by other output is connected to receive-transmit MW head control input, and the second type user’s station MW downconverter has auxiliary AGC loop.

Technical result: provides essential increase in a dynamic range at USs receivers inputs, levels difference reduction of the signals radiated by transmitters of video information gathering posts receive-transmit blocks transmitters and, thus, CS segments receivers necessary dynamic range reduction. The device survive during heavy rains, but it can be used and in usual conditions as the given device allows to lower expenses for installation of system and to lower operational expenses.

THE UKRAINIAN PATENT № 54275, 10.11.2010

P. Ksenzenko, M. Boichenko, P. Himich,

“ROKS”-company

The invention concerns multichannel broadcasting networks (including to multichannel single frequency synchronous broadcasting networks – multichannel SFN) in which signaling from the central station to base stations is carried out on multichannel radio relay lines (RRL).

The method according to which earth television broadcasting signals are relayed intra the channel, more particularly, by means of an intrachannel repeater which according to an earth television broadcasting method receives, gains and transmits a signal in the same frequencies band is known, and radio-frequency (RF) broadcasting signal which is transmitted by the main transmitter, at first will be converted in a repeater to a baseband signal, then back in RF signal, and then will once again be converted upwards on frequency and transmitted in the same frequencies band.

The high-quality equalizer deletes noise and the detained in time signal copies which get in a protective interval and which arise as result of a multibeam mode propagation in a radio channel between the transmitter and an intrachannel repeater from a baseband signal. By means of feedback signal processing which gets into the receiver because of rather weak isolation between transmit and receive antennas, in a repeater the received baseband signal moves in time. The shifted in time baseband signal again will be converted in RF broadcasting signal so that the same input and output signal was relayed in the channel [1].

In the specified broadcasting system the main transmitter and an intrachannel repeater relative positioning depends on district landscape and system service zone geometry. Usually a repeater place so that a weak broadcasting signal which is received by a repeater from the main transmitter, it was processed for the gaining purpose, and at the main transmitter service zone expense would extend. In the intrachannel repeaters extended at present, which often name Gap-Filler, the received signal will be converted to an intermediate frequency signal on which it is filtered and amplifies in amplifiers with automatic gain control, and then will be converted again upwards on frequency and radiated as a target signal.

The specified method lack is that in the given system relaying is carried out on intermediate frequency, therefore those noise and the signal detained copies which result from multibeam propagation and which in an explicit form are present only at a baseband signal cannot be removed from a signal. Thus, a useful signal copies shifted in time will be broadcasted back on-air together with the deformed signal main copy which distortions are caused by frequency fading action. Some user’s receivers sensitivity which perceive these distortions as additional noise (as these signals are not synchronized with the main transmitter signal) thereby decreases.

Relayed signals have an uncertain time lag which is a hardware delay in a repeater that is some synchronization infringement with the main transmitter is shown. At the repeater work expense a signal level in service zones shadowed sites increases, but synchronization with the basic transmitter signal can appear broken. On the shaded site border user’s receivers can receive as a signal transmitted by the basic transmitter, and a signal transmitted by an intrachannel repeater. There is a danger of that for these receivers the delay dispersion size will exceed protective interval duration, and signal receiving becomes impossible. In multichannel SFN this problem becomes even more essential as delays on different channels frequencies will have different size.

The lack which is shown at this method use in multichannel single frequency synchronous networks consists that the repeater with signal processing in the baseband is unequivocally single-channel. In a multichannel network to service only one shadowed site it will be necessary to apply repeaters in quantity which is equal to channels quantity. Thus the repeaters block becomes bulky and very expensive. Besides, at a considerable transmitting and receiving antennas quantity which take places in one place, it is very difficult to provide necessary isolation between them.

In this case in system there is necessary one more frequencies band use and user’s receivers of two types, but thus system there are more flexible in construction, and multichannel repeaters which in it are used, will be much cheaper, than repeaters blocks consisting of separate single-channel repeaters. Besides, thanks to other working frequencies band, repeaters in no way will not disturb to multichannel SFN work.

As the closest method which is used on the same appointment, as declared, the method at which sound (audio), video, and also other digital information transfer within certain geographical district with communication channels set creation at very low expenses possibility is provided. The given system application technical result is satellite signaling techniques application possibility for earth signaling. The earth communication system includes, at least, one local land repeater (LTS) which is established on a mast or other basic design. Everyone LTS is completed with high-frequency communication equipment which basically corresponds to the usual geostationary satellite equipment, for digital transmission of the visual and sound information transferred in L – a range (1-2 GHz), S – a range (2-4 GHz) or in higher frequencies ranges at rather low level of a radiated signal. For transfer realization mainly in a horizontal plane it is desirable to use the omnidirectional antenna [2]. The specified method is chosen as a prototype.

The resulted method lack is that fact that the practical specified scheme embodiment is represented problematic. The main obstacle is that omnidirectional transferring antennas are difficult for making with beamwidth in a vertical plane which would be less than 5 deg. Thus, a those user’s stations (USs) antennas which are approximately as equals distances from adjacent LTS, will receive signals at once several transmitters that does reception impossible. And at presence even the weak reflected signals the interference with adjacent channels picture will appear very difficult. Therefore in actual practice which are characteristic for the earth communication, the given network organization scheme cannot be put into practice. The network can be executed as multichannel SFN, but in this case transferring aerials diversity on height is deprived sense. In this case transmitters MNR work in one frequencies band but that they did not create mutual disturbances each other, the space diversity principle is used. It is clear that in this case at use of the equipment for a satellite broadcasting it is impossible to carry out a continuous covering of the service zone occupying the big space. Such scheme is suitable only for service of the small settlements chain which service zone are not supposed, i.e. It can be applied only in specific conditions.

Thus, to the reasons which prevent with expected technical result achievement at use of a known method, that at creation of a multichannel single frequency synchronous broadcasting network (multichannel SFN) in which are used one CS and several BSs, having rather small radiated power (it is considerable smaller, than the television centers transmitters power), it is necessary to build a network in the form of several mutually overlapping cells concerns. Thus the frequencies of all channels used for synchronous transfer in all network cells, coincide. At occurrence in cells of the shaded sites their liquidation at the expense of blocks from single-channel Gap-Filler is inefficient, as quantity Gap-Filler will be equal to broadcasting channels quantity, and the repeaters block will appear very bulky and expensive. The CS and BSs transmitting antennas diversity on height use does not give expected result as it is difficult to make antennas with beamwidth in a vertical plane smaller 5 deg. CS and BSs diversity in space across so that they did not disturb each other (on distance more than cell radius) does not give possibility to form a continuous cover zone.

The task in view dares because in a broadcasting network use the multichannel repeaters which signals divide by their transmitting aerials diversity on height or in space, and also into a multichannel broadcasting network enter the multichannel co-channels repeaters working in a radio relay communication lines frequency band which connect among themselves the network central station (CS) with base stations (BS) set, and co-channels repeaters receiving antennas place in a beam space which is formed the radio relay communication line transmitting antenna, and co-channels repeaters transmitting antennas place in space so that their beams completely would cover the shaded sites and provided signal distribution to bigger zone to the transmitting antenna radiation direction, and in a band of the radio relay communication line user’s stations receivers work, and receiving and signaling by co-channels repeaters is conducted on the same frequencies coinciding with frequencies of radio relay communication lines, co-channels repeaters receive the signals extending in one wireless transfer environment, namely, – in radio relay lines (RRL) radio channels, and transfer them in other environment – in a wireless network of a multichannel television broadcasting, and in a network of a multichannel broadcasting user’s stations of two types are used: stations which receive signals from both central and base stations, and the stations receiving signals from multichannel co-channels repeaters.

Repeaters receive antennas settle down within the volume limited from the outside to a cone surface, which has the transmitting RRS antenna beam form (established in transmitter CS location), and from within – an ellipsoid of rotation surface, which diameter (in the RRL middle) it is equal in the widest place of 80 % from diameter a Fresnel zone diameter, and on beam continuation for RRL limits (further to reception RRS which had on BS tower) – only a cone surface. The transmitting antenna installation site gets out so that it was possible to provide the cell shaded site covering and signal distribution to the greatest zone in the repeater transmitting antenna radiation direction.

Proceeding from listed, the resulted known signs association and a declared method essential signs set provides at the introduction expense in multichannel broadcasting network equipment (mainly multichannel single frequency synchronous network – multichannel SFN) co-channels repeaters structure shadowed sites in network cells liquidation , and also a network cover zone as a whole limits expansion.

Taking into account all resulted before reasons, in the system constructed on the declared method basis it is recommended to carry out communication between CS and BS set on the radio relay lines working in other, higher frequencies range. Higher frequencies range use yields the best result as here the relative frequencies bandwidth occupied with a multichannel signal, becomes smaller, therefore and a multichannel repeater realization will be easier.

The declared network construction method allows essentially increase possibilities of a multichannel single frequency synchronous broadcasting network (multichannel SFN) at the expense of additional co-channel in relation to RRL channels repeaters introduction. Application of the given repeaters supplements application usual Gap-Filler which because of inherent in them band narrowity can appear limited in multichannel SFN. Co-channels repeaters will help to provide with a service zone signal “the shaded” sites and it is essential to expand the service zone sizes in some directions.

The offered invention essence is explained by the drawing represented on Fig.: – The system block diagram in which according to a declared shadowed area liquidation method at the expense of introduction in network a co-channel repeater is carried out. On Fig. the broadcasting network consisting from one CS and several BSs (on the scheme one of them is conditionally shown only) which, radiating a signal in all directions is represented, form mutually overlapping cells.

In structure CS and several BSs omnidirectional antennas or sector antennas systems are used. CS can communicate several BSs by means of any communication lines: radio (radio relay), cable or fiber-optic. In this case it is a question of networks in which communication between CS and any of working in network BSs is carried out by means of radio relay lines (RRL). The each of RRL structure includes transmitting radio relay stations (transmitting RRSs) which antennas usually place on the same tower on which it is established antenna CS and receiving radio relay stations (receiving RRSs) which antennas place on BS towers. On fig. pos. 1 is a one of BS cells.

The repeater 5 receiving antenna place in the volume limited to the transmitting antenna RRS 3 beamform. The transmitting RRS antenna directed action factor (DAF) is calculated under the formula:

DAF = 32000 / (2θ3x * 2θ3y),

where 2θ3x and 2θ3y is the real orientation diagram main petal width on half power level (- 3 дБ) in two mutually perpendicular planes x and y (on Fig. the beamwidth in a horizontal plane 2θ3x is shown). The transmitting RRS antenna beamwidth can be any (2θ3x = 30… 360 deg.).

The declared method essence consists that the repeater 5 receiving antenna (Fig.) place in the middle of the volume occupied with a beam which is radiated by the transmitting RRS antenna. At antennas with the narrow diagram of an orientation use this area usually has the form of a cone with a corner in top which is equal 2θ3x = 2θ3y. Generally equality 2θ3x = 2θ3y is not observed, and the beam gets more difficult form, and the repeater antenna can take places as along RRL (between transmitting and receiving RRS), and on its continuation (Fig.). At the aerial 5 along RRL placing the geometrical place of its possible arrangement points is in the volume limited to two surfaces: a cone surface outside and an extended ellipsoid of rotation surface 6 from within. The ellipsoid of rotation width in the widest part (in the RRL middle) pays off as 80 % from a Fresnel zone width. If not to suppose the repeater reception antenna placing in the specified zone (on Fig. It is shaded) losses at the expense of a gleam for beam reduction passage can be neglected. The Fresnel zone radius (or diameter) size depends on distance between antennas and frequency.

The declared method in practice can be realized thus. In any of the points located in formed by CS and BSs cells, shadowed sites 7 can arise. It shadow is caused by that on a site behind an obstacle 8 having considerable in comparison with the wave length, and also height, comparable with CS or BS tower height, radio-waves propagation is complicated or at all it is impossible. In such cases in usual SFN for maintenance with a signal being in a shadowed zone subscribers use Gap-Filler. However in itself Gap-Filler has the limited working frequencies band, therefore for the task in view decision, i.e. for “flare” only one shadowed site, in multichannel SFN it should to use considerable quantity Gap-Filler. In this case the repeaters block will appear excessively bulky and expensive. Besides, to isolate among themselves a considerable quantity of the receiving and transmitting antennas belonging several Gap-Filler, it is not obviously possible. To realize a broadband repeater it is possible only on higher frequencies because on higher frequencies at the same absolute bandwidth occupied with a multichannel signal, the relative bandwidth will be less. According to a declared method, for each shadowed site only one co-channel group repeater 9 which should work in higher frequencies range (in a range used RRL), than CS and BSs transmitters is used. Thus the repeater 5 receive antenna place in space of the beam formed by the transmitting RRS antenna, and transmitting antenna 10 place in space so that its beam has completely covered a shade site 7 and thus as much as possible would expand all network cover zone in the antenna 10 radiation direction (a zone 13). Antennas 10 can have the diversified diagrams of an orientation: circular, in the form of sector or the narrow diagram of an orientation. The repeater 9 transmit and receive bands completely coincide, therefore, as well as in case of Gap-Filler traditional application, a relative positioning and diagrams of an orientation receive 5 and transmit 10 antennas should be chosen so that between them sufficient isolation degree would be provided. Receiving and transmitting are conducted in a frequencies band which coincides with RRL working band. In the same band the US 11 receivers work also. Thus, in a network two types of the US are used: stations 12 which receive the multichannel broadcasting signals transmitted by CS or BSs, and stations 11 which receive signals from co-channels repeaters 10 transmitters. These signals are radiated in sector 13 by repeaters 10 antennas which work in a radio relay lines frequencies band. Co-channels repeaters also receive and transmit in the same frequencies band. Their difference from usual Gap-Filler consists that they receive the signals extended in one wireless transfer environment, namely, – in radio relay lines (RRL) radio channels, and transmit them in other environment – on-air broadcasting environment. Therefore even at full received and transmitted by them signals parameters coincidence they should be considered as co-channels repeaters. For shadowed sites liquidation and increases in all network service zone sizes, in the beams formed by transmitting RRS antennas which take places on CS, except for 80 % of a Fresnel zone, establish co-channels multichannel repeaters receive antennas. Thus repeater transmitting antennas place in space so that to transmit a signal in a cells shadowed site and as much as possible to expand a service zone. Receiving and transmitting by co-channels repeaters is conducted on the same frequencies. In a network two types of user’s receivers are used: for reception of the signals transmitted by CS and several BSs; for reception of the signals transmitted by co-channels multichannel repeaters.

Fig.1 The method of shadowed areas elimination and the service zone expansion by the co-channels repeaters using

The multichannel data transmission network with co-channels repeaters use can be constructed according to such initial data:

Proceeding from specified, the broadcasting in a network is carried out in a frequencies band 5705 – 5825 MHz with use of a 12-channels broadcasting signal (mainly with transfer of separate channels to a synchronous mode) at 8 MHz channel width and 10MHz multiplexing frequencies grid step. BSs quantity in a broadcasting network is defined in the cover zone sizes and configuration. The broadcasting network answering to the listed initial data construction is quite real.

Referencies:

1. The USA Patent №2004/0237117A1, pub. 2004.11.25
2. The Patent of the Russian Federation № 2189702, pub. 9.20.2006, bul. №26.

The applicant, general director of Company “ROKS” Ksenzenko P. J.

The invention formula

1. The method of shadowed areas elimination and a service zone expansion by using of the co-channels repeaters which assumes the multichannel repeaters application which signals are divided by their transmitting antennas diversity on height or in the space, different by that the co-channels multichannel repeater working in a radio relay communication lines frequencies band which connect among themselves the network central station (CS) with include in a broadcasting network base stations (BSs), and co-channels repeaters receive antennas place in the beam space formed by the radio relay communication line transmitting station antenna, and co-channels repeaters transmitting antennas have in space so that their beams completely covered the shadowed areas and provided signal distribution to whenever possible big zone to the repeater transmitting antenna radiation direction, and in the radio relay communication line frequencies band the user’s stations receivers work.
2. The method of the shadowed areas liquidation and service zone expantion by using of the co-channels repeaters at the expense of co-channels repeaters application, under item 1, different that receiving and transmitting by co-channels repeaters are conducted on the same frequencies which coincide with frequencies of radio relay communication lines.
3. The method of the shadowed areas liquidation and service zone expansion by the co-channels repeaters using at the expense of co-channels repeaters application, under item 1, different that co-channels repeaters accept the signals extended in one wireless transfer environment, namely, – in radio relay line (RRL) radio channels, and transfer them in other environment – on a multichannel television broadcasting wireless network environment.
4. The method of the shadowed areas liquidation and service zone expansion by using of the co-channels repeaters at the expense of co-channels repeaters application, under item 1, different that in a multichannel broadcasting network the user’s stations which accept signals or from the central station and base stations, or from co-channels multichannel repeaters use.

The applicant, general director of Company “ROKS” Ksenzenko P. J.

ABSTRACT

Object of the invention: The method of the shadowed areas liquidation and service zone expansion by the co-channels repeaters using at the expense of co-channels repeaters application.

Application branch: the Invention concerns multichannel broadcasting networks (including to multichannel single frequency synchronous broadcasting networks – multichannel SFN) in which signaling from the central station to base stations is carried out on multichannel radio relay lines (RRL).

An invention essence: The multichannel repeaters application in broadcasting networks, which signals divide by their transmitting antennas diversity on height or in space, and also co-channels multichannel repeaters in a broadcasting network working in a radio relay communication lines frequencies band which connect among themselves the network central station (CS) with base stations (BSs), and co-channels repeaters receive antennas place inclusion in space of the beam formed by the radio relay communication line transmitting station antenna, and co-channels repeaters transmitting antennas place in space so that their beams completely covered the shadowed areas and provided signal distribution to whenever possible big zone to the repeater transmitting antenna radiation direction, and in the radio relay communication line frequencies band the user’s stations receivers work, receiving and transmitting by co-channels repeaters is conducted on the same frequencies which coincide with frequencies of radio relay communication lines, co-channels repeaters accept signals which extend in one wireless transfer environment, namely, – in radio relay lines (RRL) radio channels, and transfer them in other environment – on wireless multichannel television broadcasting network environment, and in a multichannel broadcasting network the user’s stations accepting signals or from the central station and base stations, or from co-channels multichannel repeaters are used.

Technical result: At the expense of the method assuming introduction in a multichannel broadcasting network (mainly multichannel single frequency synchronous network – multichannel SFN) equipment structure co-channels repeaters shadowed areas in network cells are liquidated, and also network as a whole borders extend.

UKRAINIAN PATENT № 36562, 27.10.2008

P. Ksenzenko, M. Boichenko, P. Himich,

payday loans with easy approval
A. May, V. Yakimenko

“ROKS”-company

The invention concerns to special microwave communication technics which provides data transfer and reception on radio communication channels. The device in which the central station structure includes at least one base station WiMAX with sector antennas which quantity does not exceed quantity of the base stations WiMAX connected to server (main system computer) and the access server of the central station has access to a given external network, for example, the Internet networks with an opportunity of data transmission between subsystems DVB-S and WiMAX thus subsystems WiMAX and DVB-S servers are connected to Central Station server access port (1) is known.

Lack of the specified device is that the increase in quantity of interactive subscribers is reached due to addition of additional subsystems structurally not connected with the basic system in the form of data reception and transmission “point-to-multipoint” networks that does system of more bulky increasing served subscribers quantity but not adding thus of any new functions. Besides in considered system opportunities of services only TV broadcasting independed granting are limited. From the resulted device design it is completely not clear how in the given system transmitter it is possible to organize a multifrequency group signal and transfer up to 200 TV programs, in view of that fact, that at use of standard DVB-S transferred on one carrier signals quantity does not exceed eight. In the same case when data in the direct channel multiplex with a television broadcasting signals in transport stream MPEG-2 uniform to separate television programs from data downstream it is possible only by means of dear professional receiver-decriptor instead of household tuner DVB-S that economically it is not justified completely.

Most to relatives from the devices applied to the same purpose as declared the device which includes central and user’s stations is, and the structure of the Central Station includes at least one receive-transmit trunk including the transmitter which output through diplexer is connected to the antenna, and the receive path (downconverter) which input through diplexer is connected to the antenna, and an output – to the divider block.

The head reception station including the downconverter which output is connected to an input of the divider block which outputs are connected to demodulation blocks, and a computer to which demodulation blocks (2) are connected is entered into structure of the Central Station. The specified device is chosen as the prototype.

In the specified device one transmitter on which from an information server one digital stream acts is used. As bit rate of the given digital stream is limited (does not exceed 41 Mbps) also opportunities of the information great volumes transfer also are limited. Roughly is up to 10 digital TV programs at compression under standard MPEG-2 or up to 15 programs at compression MPEG-4 AVC. If to consider, that in the same datastream should be transferred also and data the Internet becomes obvious that the system is rigidly limited on volume of the transfered information. As a matter of fact, it is intended only for Internet data transmission, and its application for TV broadcasting has applied character.

To the reasons which interfere with achievement of expected technical result at use of the known device the impossibility of video information great volumes transfer maintenance in the central station direction and reception of this information by the Central Station concerns. The known device is not capable to solve a specified problem because in it the organization of a video information gathering system in any kind is not stipulated, and in structure of its Central Station opportunities for branch of a video information gathering system from signals of return channels signals of return data transmission network are not stipulated.

The task in view is solved owing to that the declared device has the Central Station and a video information gathering system thus the Central Station has the antenna system including N sector antennas according to which the Central Station has N segments each of which includes the sector antenna which is connected by an input-output with diplexer which is connected by an output to the downconverter which is connected by an output to a multichannel power divider which by N outputs is connected to the modem which is connected by an input-output to a Central Station digital platform, and by an output is connected to the combiner which is connected by an output with diplexer, and the combiner is connected to a power divider output which is connected by an input to the multichannel combiner which by N outputs is connected to modulators of Central Station remultiplexing block, and the multichannel power divider of each of segments is connected by an output to the receiver of a video information gathering system, the digital platform of the Central Station is connected by an output to the Central Station computer, and the video information gatheting system includes a video information gatheting post both transferring stationary and mobile video information gathering points, and the video information gathering post is connected to the Central Station.

Proceeding from specified below, combination of the specified attributes and set of essential attributes of the multimedia system incorporated with a video information gathering system provides occurrence of new invention technical properties which are connected with maintenance of increase in the transferred information volume due to sector antennas system and a frequencies reuse, formations in transmitters of multifrequency group signals which consist of several digital TV radio-frequency channels and several direct channels of information signals transfer, opportunities of two types user’s service stations, namely, – for TV broadcasting signals receiving and transmit/receive of information reports and for TV broadcasting signals receiving essential function expansion due to addition of the video information gathering system having two-level structure.

Ability of a video information great volumes gathering raises consumer qualities of multimedia systems which are usually intended for TV and radio broadcastings, and also an exchange of information reports between the Central Station and user’s stations set. Needs for a video information great volumes gathering which acts from a plenty of video information gathering points (cameras placing points) to a video information gathering post and further to the system Central Station can be caused by necessity of the videoreporting or video surveillance realization behind the distributed objects lot. Connection in one system of multimedia system and a video information gathering system functions allows to raise efficiency of the specified device use considerably.

The essence of the offered invention is explained by the Fig. on which the multimedia system incorporated with a video information gathering system block diagram is represented.

The multimedia system incorporated with a video information gathering system consists of following basic elements (Fig.): the Central Station 1, a video information gathering system 2, and user’s stations 3.

The Central Station (CS) 1 consists of segments 4 which quantity depends on CS antenna system sectors quantity (from 1 up to 8 sectors). Each of segments 4 consists of the sector antenna 5 which on an input is connected by the upconverter 7, and on an output – with the downconverter 8. The upconverter is connected by 8 output to a multichannel power divider 9 which by N outputs is connected to the modem 10, and by an output is connected to the receiver of a video information gathering system. The modem 10 is connected by input-output to a digital platform 12, by an output is connected to the combiner 11 which is connected by an output to the upconverter 7. The digital platform 12 by N inputs-outputs is connected to modems 10 of N CS segments 4, and by an output is connected to main CS computer (server) which has an output to external distributive networks. The multichannel CS power divider 13 by N outputs is connected to combiners 11 of N segments 4, and by an input is connected to CS multichannel combiner 14 which by N inputs is connected with N remultiplexing station modulators.

The video information gathering system 2 includes a video information gathering post 15 which is connected through air-or cable communication line with transmitting stationary 16 or only on radio lines with a mobile video information gathering point 17 and on a radio channel is connected with CS 1. The multimedia system incorporated with a video information gathering system (UWMS) (Fig.) operates as follows.

1. A television broadcasting signals (TV) formation

TV signals are formed by remultiplexing station (on Fig. 1 it is not represented). The remultiplexing station usually represents a teleport which receives signals of satellite, cable, air TV, and also signals from local studio. On CS these signals are properly processed. This processing includes decoding those signals which are coded by conditional access system (descrambling), remultiplexing transport streams with the purpose of new TV programs multiplexes formation and scrambling these streams by own system of address coding. After the specified operations necessary for formation of scrambling streams DVB-S the received datastreams are sent on modulators on which outputs obtain carriers modulated by signals of multiprogramm TV.

Modulated carriers are united in a multifrequency group signal by multichannel combiner CS 14. Further the group signal divides on power on N parts (by quantity of system segments) by means of a power divider 13. On power divider 13 outputs it is formed N spears of a group signal, each of which goes on the combiner 11 of one
CS segment 4.

2. The direct data link (a downstream) formation.

The downstream is formed by a CS modem 10 (WMTS) transmitting part. In it DVB data packages with division on time (TDM) modulate preliminary established carrier forming the direct data link. This signal is united by means of the combiner 11 with a group broadcast signal forming the full transfer direct channel for the given sector on intermediate frequency. Further this signal will be upconverted to a necessary frequencies range, amplifies, and having passed through diplexer 6 is radiated by the sector antenna 5 in the form of a beam in width 360 deg./N (where N – quantity of antenna system sectors). The signal is received by user’s stations (US1 – USn) 3, and stations of kind US1 accept only broadcast signals and stations of kind USn accept both signals of an broadcasting and a signal of the direct data link.

3. The upstream transfer.

The upstream signals are transferred by stations of type USn in direction CS. Thus, methods of frequency and time multiplexing (method FDMA/TDMA) are used. At use of such distribution method a quantity the US works on one frequency and transfers messages in the form of software packages to the CS modem 10 command. These commands are built in structure of the downstream data channel in the form of the special channel (the channel of management). Such collision-free work of the US by transfer of upstream data packages is reached. By the same principle other USs similar USn which work on other frequency work also and also those from them which belong to CS segments 4 with numbers 2 … N.

4. Signaling by a video information gathering system.

A video information gathering system has two-level structure. Necessity of such construction is caused by that the signals transferred stationary 16 or mobile 17 video information gathering points can correspond to different standards, for example, DBS – for analog points and DVB-T – for digital. Besides for signals of the first level it is difficult to obtain sufficient range by transfer which would allow to transfer directly a signal on CS because of the video information gathering points transmitters limited power (especially mobile), a low arrangement of transmitting antennas, and also complex radio wave propagation conditions (absence of ” line-of-sight ” mode, the big number of the reflected signals presence, etc.). Inclusion in system structure of the video information gathering posts quantity which settle down so that for them ” line-of-sight ” mode with CS was provided allows to solve this problem. The receivers which are a video information gathering post 15 part receive and process the various signals acting from video information gathering points, and will transform them to a uniform kind (to a kind of transport streams (TS) of DVB standard). Further these TSs are multiplexed in the uniform datastream which modulates carrier on intermediate frequency. Then this signal will be upconverted on frequency and amplifies by the powerful upconverter (BUC) for the further transfer on a radio channel in direction CS.

On each CS segment 4 signals from USn and video information gathering posts15 which are located in an CS antenna 5 operative range act. The signals received by the antenna through diplexer 6 act on low noise downconverter 8 in which they amplify and will be converted to signals of intermediate frequency. Signals of intermediate frequency act on a multichannel power divider 9. This divider has outputs quantity which is equal to quantity of the CS modem 10 inputs plus one more output from which one of the received signal spears goes to video information gathering system receivers (on Fig. are not represented). As these receivers usual tuners DVB-S can be used.

The inputs quantity of the CS modem 10 is equal to quantity of frequencies to which transfer USn (method FDMA). Signals that are received and processed by the CS modem 10 form the return data link (upstream).

All operating mode organization of a data transmission network are assigned to CS modems 10 which quantity is equal to quantity of segments 4. The separate modems 10 traffics are united by CS digital platform 12, and the incorporated traffic acts on a computer (the main system computer – a server) which provides interaction with external data transmission networks.

The multimedia system incorporated with a video information gathering system (Fig.), can be realized on the basis of multimedia system MVDDS (MITRIS) which uses for transmitting the frequencies 11.7-12.5 GHz, and for receiving – 10.7-11.5 GHz. As CS modem it is used WMTS systems DOCSIS, for example, BSR2000 Motorola. By transfer of high-speed upstream with data rates till 10.24 Mbps by means of the given system it can be served in an interactive mode up to 2560 subscribers. And the maximum quantity of subscribers can reach 24000. To advantages of such system construction it is possible to carry the following: compatibility broadcast and interactive user’s receivers within one system. In view of that interactive user’s stations receivers in some times more dear that broadcast receivers the subscriber to whom “interactivity” it is not necessary can choose the broadcast receiver which will give to it an opportunity to receive 128 TV programs. Such approach to construction of system allows to carry out its stage-by-stage introduction in build, namely:

– at the first stage the system can be increased by addition of additional WMTS in those sectors in which the quantity of subscribers is great. Limiting opportunities of system are defined by opportunities of a digital platform;

United Wireless Multimedia System (UWMS)

Fig. 1

– maximal use of the devices which are being mass production and developed earlier that will allow to lower cost of system and to raise its suitability to scaling. The offered system allows to give very wide complex of services, namely:

– multichannel (up to 128 TVC) digital TV;

– high-speed the Internet both in direct and in the return directions;

– operative reception by law enforcement bodies, bodies of local authorities and self-management, and also local television studioes of a necessary video information great volumes;

– on occassion the video information gathering system can be very useful to management of complex technological processes on manufactures which separate divisions can be disseminated on all settlement.

The declared system is quite sufficient for service of the average sizes town and in a megalopolic – for the big urban disrtrict. The declared system can give to Law Enforcement Bodies and Security Service of Traffic up to 640 video surveillance points from which transfer of high-quality images in real time is constantly conducted.

For Local Authorities – an opportunity constantly to conduct the reporting on their work it is direct from boardrooms owing to what citizens have an opportunity to receive the operative information on their work.

For local studios of TV broadcasting are constant videoreporting posts from theatrical and concert halls, stadiums and other sports constructions. And the reporting can be conducted at once by eight television cameras, in particular from mobile points, and also by wireless cameras transmitters.

Referencies:

1. Патент Украины №23044, Бюл. №6, 2007г.
2. Патент Украины №51495, Бюл. №1, 2005г. The general director of Joint-Stock Company ” ROKS ” P. Ksenzenko

The invention formula.

The multimedia system incorporated with a video information gathering system (UWMS) which includes the Central Station, thus the Central Station includes at least one receive/transmit trunk which includes the transmitter which output through diplexer is connected to the antenna, and a path of reception (downconverter) which input through diplexer is connected to the antenna, and an output – to the divider block, and in the Central Station structure the head receiving station which includes the downconverter which output is connected to an input of the divider block of which outputs are connected to blocks of demodulation, and a computer to which demodulation blocks are connected which differs that includes the Central Station and a video information gathering system is entered, thus the central station has the antenna system consisting from N sector antennas according to which the Central Station has N segments each of which includes the sector antenna which is connected by an input-output with diplexer, connected on an output with the downconverter which on an output is connected to a multichannel power divider which by N outputs is connected to the modem which by an input-output is connected to a digital platform of the Central Station, and by an output is connected to the combiner which is connected by an output with diplexer, and the combiner is connected to a power divider output which is connected by an input to the multichannel combiner, which by N inputs is connected to the Central Station block remultiplexing modulators, and the multichannel power divider of each segment is connected by an output to the receiver of a video information gathering system, the digital platform of the Central Station is connected by an output to the Central Station computer, and a video information gathering system includes a video information gathering post and stationary or mobile points of a video information gathering, thus video information gathering points are connected to a video information gathering post, and the video information gathering post is connected to the Central Station.

The general director of Joint-Stock Company ” ROKS ” P. Ksenzenko

ABSTRACT

Object of useful model: the multimedia system incorporated with a video information gathering system (UWMS).

The Scope: the special microwave communication technics providing data transfer and reception on radio communication channels.

An essence of useful model: the multimedia system consists of the Central Station and a video information gathering system, thus the Central Station has antenna system, which includes N sector antennas according to which the Central Station has N segments each of which includes the sector antenna which is connected by an input-output with diplexer which is connected to the downconverter which is connected by an input with a multichannel power divider which by N inputs is connected to the modem which is connected by an input-output to a Central Station digital platform, and by an output is connected to the combiner which is connected by an output with upconverter which is connected by an output with diplexer, and the combiner is connected to a power divider output which is connected by an input to the multichannel combiner which by N inputs is connected to remultiplexing block modulators, and a multichannel power divider of each segment an output connected with receiver of a video information gathering system, the digital platform of the Central Station is connected by an output to a Central Station computer, and a video information gathering system includes a video information gathering post and transmitting stationary or mobile points of a video information gathering, thus video information gathering points are connected to a video information gathering post, a video information gathering post is connected to the Central Station.

Technical result: Significant increases in the transferred information volume due to sector antennas system and frequencies reuse, formations in the digital TV transmitters multifrequency group signals consisting of several radio-frequency transfer channels and several direct channels of information signals transfer, opportunity of two types user’s station service: for TV broadcasting signals reception and information reports transmit/receive, for TV broadcasting signals reception only, essential function expansion due to connection of the video information gathering system having two-level structure.

UKRAINIAN PATENT № 24643, 10.07.2007
P. Ksenzenko, M. Boichenko, P. Himich, A. May, V. Yakimenko “ROKS”-company

The invention concerns to special microwave communication technics which provides data transfer and reception on a radio communication channels. Devices in which the transfer path in the field of microwave frequencies (MW) is executed by a principle of single-channel transmitters powers addition by means of the multiplexers formed by channel filters which are established on each of transmitters outputs, and by ferrite circulators (1,2,3) system are known. Thus frequencies bandwidth which one channel borrows, – nearby 20 MHz , and a frequencies grid step between the next channels – 28 MHz . On frequency 12 GHz channel filters with necessary characteristics can be executed on structures with high quality factor, for example, in the waveguide filters or filters on dielectric resonators form. Lack of the specified devices is that the filters used in transmitters are dear and complex in adjustment (each of channel filters demands individual adjustment), and transmitters quantity to equally radio channels quantity. With the purpose of signal losses prevention the bulky and dear microwave transmitters block should be located near to the transmitting antenna that demands significant capital expenses at equipment installation. Moreover, at relaying a multichannel signal on other base station (BS) the complete set of transmitters and multiplexers should be repeated. At system installation it configuration change (change of the radio channels order and frequencies) is realized with greater difficulties. In most of the known device which has the same purpose as declared is included the programmed converter-composer of an intermediate frequency group signal which is connected to frequency modulating and transmitting blocks.

The transmitter, in turn, is connected to the antenna (4). In the specified device, unlike resulted earlier, for several channels transfer the group broadband transmitter is applied. The transmitter represents the broadband powerful frequency upconverter (BUC) which is used for an intermediate frequencies spectrum convertion in a microwave range and corresponding output signal amplifying. To the reasons which interfere with achievement of expected technical result at use of the known device the impossibility of reception zone expantion maintenance for repeaters in particular concerns. Repeaters cannot be placed on distances from the central station ( CS ) which exceed the service zone size (they should be placed inside of a cell). For reception of a communication opportunity with next BS it is necessary to use fiber-optic communication lines ( FOCL ) or cable lines. The lining of cables or FOCLs is associated with significant capital expenses and in the generated city infrastructure – is simply impossible. Thus, to solve a task in view, i.e. to expand a service zone of all cellular system and to increase quantity of subscribers by means of the specified device (prototype) it is impossible. The task in view is solved owing to a method according to which the declared device gets the combiner-equalizer which N inputs incorporates to outputs N quadrature modulators, and on an output is connected to an input of a multichannel power divider which by N outputs is connected with N inputs of the radio relay transmitters connected to radio relay antennas, and on M outputs is connected with M broadcast transmitters, thus everyone broadcast transmitter is connected to the antenna, and quadrature modulators carry out modulation QPSK, QAM or COFDM, adjustment of channels frequencies and signals spectra formation in an intermediate frequencies range, broadcast and radio relay transmitters work within the limits of the same frequencies range, and at M broadcast transmitters each of them is connected to M sector antennas which form antenna system. Proceeding from told, it is possible to approve with what exactly connection of the resulted attributes and also set of essential attributes of a transmitting complex provide occurrence of invention new technical opportunities which consist in essential increase in a service zone (a cover zone of cellular system) and increase in total of network users (subscribers) due to not only increases in the service zone area, but also prevention of a radioshadow sites occurrence. The decision of the given problem for existing (classical) multimedia systems MVDDS (” MITRIS “) probably exclusively by increase in transmitters power and height of antennas raising, and also increase in antennas gain factor, etc. These measures lead to growth of capital expenses and ecological pollution of territories which adjoin to a transmitter installation place. However, even these measures do not allow in conditions of greater cities with their multi-storey building to prevent radioshadow sites inside of a service zone. Potential subscribers who are within the limits of a radioshadow sites cannot be served by such system. The decision of the specified problem probably by construction of multimedia system in the cellular structure form consisting of set BS which incorporate with each other and with CS defining operation algorithm as all multimedia system.

Transmitting complex CS and BS except for the transmitter and antenna system which carry out service of own cell should have a transmitting radio relay systems quantity which carry out communication CS with BS and BS with BS by means of radio relay lines ( RRL ). As the volume of the digital information which compose of multiprogramme TV, Internet, and other services is very great for its transfer to the subscribers who are settling down inside of service zones (cells) CS and BS it is necessary to use broadband radio channels and a greater general bandwidth of the frequencies borrowed on air. The same information volumes are transferred also in a direction from CS to several BS . Considering told, on the foreground the problem of a frequency resource economy acts. The essence of the offered invention is explained by means of Fig .1 and Fig .2 on which in the block diagrams form transmitting complexes with elements making them and their interrelation are represented.

The transmitting complex of the multimedia system central and base stations having cellular structure ” MITRIS-CS ” (Fig .1) includes quadrature modulators 1 which are connected by the outputs with N inputs of the combiner-equalizer 2, it, in turn, is connected by an output to an input of a multichannel power divider 3 which on an output is connected with N inputs of radio relay transmitters 4 and an input broadcast transmitter 5, and radio relay transmitters 4 are connected to antennas 6, while broadcast transmitter 5 on an output is connected to the antenna 7, thus the antenna is executed with the circular orientation diagram.

Transmitting complex ” MITRIS – CS ” ( Fig .2) has the same construction, as well as the transmitting complex represented on Fig .1 except that in addition includes M broadcast transmitters 5 which are connected with M additional outputs of a multichannel power divider 3 and with M sector antennas 9 of antenna systems 7. The multichannel power divider 3 thus has total of outputs N+M.

Transmitting complex ” MITRIS – CS ” (Fig .1) works thus. Digital streams MPEG-2 which represent remultiplexing and scrambling transport streams of multiprogramme TV, Internet data, and other digital services act on quadrature modulators 1 by means of which carriers digital modulation QPSK, QAM or COFDM in an intermediate frequencies range is carried out . The central frequencies of radio channels can be chosen by any way as a result to receive a group signal with an optimum frequencies grid. All spectral characteristics of the modulated signals such as, for example, radio channel bandwidth, a power spectrum slopes steepness, and others also are formed in modulators 1. The multichannel group signal is formed in the multichannel combiner-equalizer 2. On each of the combiner-equalizer 2 inputs the amplifiers executed under the ALC scheme with a changeable threshold level are established. Such scheme allows to establish independently an everyone carrier level in a group signal and also supports this level to constants on the device output at some change of input signals levels. After amplifying signals are united by the passive binary combiner on the basis of Wilkinson briges . From an output of the combiner-equalizer the multichannel group signal acts on an input multichannel (conditionally on Fig .1 – three-channel) power divider 3. On an input of this device the passive multichannel power divider is placed. It divides power of a multichannel group signal creating necessary quantity of its spears. Each of signals amplifies and adjusted on a level by means of amplifiers. On outputs of a divider are established injectors by means of which power supply voltage from power supplies move together with a signal on radio-frequency cables on powerful upconverters – transmitters 4 (BUC). The copies of a multichannel group signal received thus move on broadcast transmitter 5 and the antenna 7 which radiates in all directions of space in a horizontal plane covering a cell which adjoins to CS or BS . Other copies of a group signal, also together with supply voltage, act on radio relay transmitters 4 and further on RRS transmitters antennas 6. Broadcast transmitter 5 and radio relay transmitters 4 (with antennas accordingly 7 and 6) can work in the same frequencies range. It is possible owing to much greater gain factor of the directed antennas transmitting RRS concerning antennas with the wide orientation diagram. Owing to greater approximately on 30 dB gain factor of antennas 6 will be greater and a level equivalent isotropic radiated power since it is equal to product of transmitter output power on transmitting antenna gain factor. The signal/noise rate for receiver RRS which belongs to the next cell with a stock can be up to level 20 dB. Thus, at a corresponding choice of a RRS receiver sensitivity level the levels of the signals radiated by the antenna 7 and accepted by receiver RRS will be below a level of receiver own and these signals will not stir to its work. This circumstance is important because owing to it the essential economy of a frequency resource is reached at cellular structure formation. Operation of transmtting complex “MITRIS – CS ” which is shown on Fig. 2 differs that the quantity of multichannel power divider 3 outputs is increased on M outputs and the antenna system 7 consisting M sector antennas 9 is generated so that to provide the necessary general orientation diagram. Advantage of such antenna system consists in an opportunity of flexible and operative change of its orientation diagram in a horizontal plane due to signals levels change on broadcast transmitters outputs and also due to different quantity and different individual orientation diagrams for each of the antennas entering into system.

Fig. 1

Fig. 2

The system with the group transmitter (BUC) has a number of unconditional advantages. Considering that the transmitter is executed in the form of the powerful upconverter all actions with a multichannel group signal can be made on intermediate frequency (advantage is necessary for giving a frequencies range in a L- band). After all necessary manipulations above a group signal (combining, division, alignment of levels, etc.) it moves on the transmitter and in the antenna. Use concerning low intermediate frequencies in a L- band allows to simplify and diversify considerably the equipment for processing a signal. For example, for combining of separate radio channels instead of the consisting microwave filters multiplexer and waveguide ferrite circulators it is possible to apply passive binary Wilkinson bridges on microstrip or coplanar lines and losses in them which make 3-15 dB can be easily filled by means of broadband amplifiers. In the specified system parameters of separate channels and the frequency plan of their relative positioning can be easily changed as no elements rigidly adjusted on certain frequencies in system are present. Owing to multisector construction of antenna system the general orientation diagram can be well adapted for requirements which are dictated by features of cell district or building. Besides as signals levels on each of M outputs of a multichannel power divider can be changed easily enough due to adjustment of each of M amplifiers gain factors established on M outputs of a multichannel power divider the general antenna system orientation diagram can to be operatively changed. In the big city such need can arise owing to new construction which has not been stipulated for the period of system installation or by virtue of other circumstances. For the organization of radio relay trunks which should connect concrete BS with others BS and CS it is enough divide power of a multichannel radio signal for reception of several parts (spears) and submit them on radio relay transmitters. Important that as it has been specified below radiorelay transmitters can borrow the same frequencies band as the broadcast transmitter. In declared system instead of frequency modulation modern kinds of digital modulation are applied, namely: QPSK (according to standard DVB-S), QAM (according to standard DVB-C), and COFDM (according to standard DVB-T). All three kinds of modulation provide use quadrature modulators. Modern microcircuits quadrature modulators which work in a L- band allow to block a range of more than one octave at satisfactory parameters of modulation. Modern frequencies synthesizers micricircuits allow to generate stable carrier with a low level of phase noise at a small frequency retuning step and in a wide retuning range which exceeds an octave. Thus, the modulators resulted on Fig .1 and Fig .2 can operatively be retuned in all established frequencies range. The main difference of a declared transmitting complex is ability to work in structure of CS and BS of the multimedia systems having cellular structure. The task in view demands introduction in system of the several transmitting radio relay stations capable to transfer signals on distances which exceed the cell sizes (CS or BS service zones).

Referencies: 1. Патент Украины № 30000, Бюл. №2, 2002г. 2. Патент Украины № 45504, Бюл. №4, 2002г. 3. Патент Украины № 55566, Бюл. №4, 3003г. 4. Патент Украины № 44933, Бюл. №3, 2002г. The general director of Joint-Stock Company ” ROKS ” P. Ksenzenko

The invention formula

1. A transmitting complex of the multimedia system central and base stations having cellular structure which includes the microwave transmitter, the antenna, the converter-combiner of a group signal which is connected to the transmitter and modulation blocks which differs that has the combiner-equalizer, which by N inputs is connected to N outputs of quadrature modulators, and by an output is connected to an input of a multichannel power divider which by N outputs is connected with N inputs of radio relay transmitters, thus everyone the broadcast transmitter is connected to the antenna.
2. A transmitting complex of the multimedia system central and base stations having cellular structure, on p .1 which differs that quadrature modulators carry out modulation QPSK, QAM or COFDM, adjustment of radio channels on frequency and formation signals spectra in a range of intermediate frequencies.
3. A transmitting complex of the multimedia system central and base stations having cellular structure, on p .1 which differs that broadcast and radio relay transmitters work within the limits of the same frequencies ranges.
4. A transmitting complex of the multimedia system central and base stations having cellular structure, on p. 1 which differs that at M broadcast transmitters each of them is connected to M sector antennas forming antenna system.

The general director of Joint-Stock Company ” ROKS ” P. Ksenzenko

ABSTRACT

Invention object: a transmitting complex of the multimedia sysnem central and base stations having cellular structure.

The Scope: the invention concerns to special microwave communication technics which provides data transfer and reception on channels of a radio communication.

An essence of useful model: the device has the combiner-equalizer which by N inputs is connected to N outputs of quadrature modulators, and on an output is connected to an input of a multichannel power divider, which on N outputs is connected with N inputs of radio relay transmitters which are connected to radio relay antennas, and on M outputs are connected to M broadcast transmitters, thus everyone broadcast transmitter is connected to the antenna, and quadrature modulators carry out modulation QPSK, QAM or COFDM, adjustment of channels on frequency and formation signals spectra in a range of intermediate frequencies, broadcast and radiorelay transmitters work within the limits of the same frequencies ranges, and at M broadcast transmitters each of them is connected to M sector antennas which form antenna system.

Technical result: the transmitting complex is capable to work as CS or BS in structure of multimedia systems which have cellular structure. Entry in system of several transmitting radio relay stations provides signaling on the distances exceeding the cell sizes (CS and BS service zones) and also provides communication with adjacent BS of cellular system.