RU126541U1 - COMMUNICATION SYSTEM USING STOCHASTIC MULTI-FREQUENCY BROADBAND CODED RADIO SIGNALS - Google Patents

Abstract

A communication system using stochastic multifrequency broadband encoded signals, comprising, on the transmitting side, a unit for generating ensembles of signals of the transmitting side, including a generator of chaotic broadband encoded signals, the input of which is connected to the output of the source data memory unit, and its outputs are connected to the corresponding inputs of the quadrature (orthogonal) generator component signals, the outputs of which are connected to the corresponding inputs of the unit for evaluating and selecting signals, the outputs of the cat They are the outputs of the block for generating ensembles of signals and are connected to the corresponding inputs of the block for selecting and storing signals, other corresponding inputs for the outputs of the switching device, the input of which is connected to the output of the information source, the outputs of the block for selecting and storing signals are connected to the corresponding inputs of the synchronization block, the output of which connected to the input of the modulator associated with the transmitting antenna, on the receiving side containing a demodulator connected to the input of the receiving antenna with the demodulator, including the signal amplifier, ADC and the quadrature splitter unit, connected in series, the output of which is the output of the demodulator and connected to the input of the synchronization unit, corresponding to the output of the receiving side signal ensembles forming unit, including a generator of chaotic broadband encoded signals, the corresponding input of which is the input of the formation unit ensembles of signals, another corresponding input of the generator of chaotic broadband encoded signals is connected

Description

The proposed utility model relates to the field of radio engineering, in particular, to communication systems using complex wideband multi-frequency encoded signals and can be used in mobile communication systems.

A known communication system based on the use of orthogonal pseudo-random sequences to smooth the spectral characteristics of the signal and provide code division of communication channels that can operate in the ultra-wideband frequency range - UWB (Ultra Wide Band) (see US patent No. 5687169, M.cl. H04J 3/06, published on November 11, 1997).

A modification of this system, which can work both in broadband and in ultra-wideband, uses C-UWB (Control Ultra Wide Band) technology, i.e. controlled ultra-wideband technology, which controls the width of the spectrum and the filling of the spectrum of a noise-like signal (see A. Golitsyn, “C-UWB Technology - the Basis for Next Generation Telecommunication Systems,” Journal of Electronics: Science, Technology, Business, No. 5, 2008 ., p. 76-81). The main feature of this system is that the information is embedded in the change in the power of the broadband signal and transmitted in the entire frequency band, and when transferring the spectrum during processing, it is transferred along with the spectrum in the receiving part.

This system offers a method of dealing with random and deliberate interference. To do this, on the transmitting side of this system, the signal is generated in digital form based on pseudorandom sequences (PSP), and on the receiving side, the signal is demodulated in a correlation manner, which allows code division of channels to be implemented.

This system comprises, on the transmitting side, a broadband noise signal generator, connected by an output to an input of a modulator, connected in turn by an output to a transmitting antenna.

On the receiving side, the system contains a receiving device connected to the input to the receiving antenna, and to the output with a first bandpass filter, the output of which is connected to the input of the amplifier, the output of which is connected to the input of the linear amplifier and limiting amplifier, the outputs of which are connected to the corresponding inputs of the multiplier, the output of the coupled with a second bandpass filter connected in series, an envelope extraction unit and a demodulator.

The determining factor in suppressing narrowband interference in this system is the frequency band of the spectrum of the interference power change, and not the frequency band occupied by the interference on the air.

However, in this system, with an increase in the distance over which the signal should be transmitted, the throughput sharply decreases due to fading in urban conditions, as well as during the movement of subscribers, which worsens the reception of signals. Therefore, the gain of such a system under conditions of multipath signal fading is possible with a decrease in the radius of the cell in the cellular system; accordingly, the number of base stations of the cellular system must be increased to ensure a sufficient level of communication quality.

Known communication systems based on OFDM-CDMA (Orthogonal Frequency Division Multiplexing - Code Division Multiple Access) technology.

An important feature of communication systems based on the above technology is the reduction of remote access interference and the influence of multipath, as well as the reduction of intersymbol interference and frequency-selective fading.

A number of systems using this technology use orthogonal Walsh-Hadamard spreading codes to generate wideband multi-frequency signals, because of their determinism, structural stealth of signals is not ensured (see Popovic Branislav M. Spreading waveforms for multi-carrier CDMA Systems. - IEEE Fifth International Symposium on Spread spectrum techniques and application (ISSSTA-98), September 2-4, South Africa, 1998).

One of the systems using the technique of generating multi-frequency wideband signals, based on OFDM-CDMA technology and using Walsh spreading codes (see US patent US 2010/0246642, M.cl. H04B 1/707, publ. 09/30/2010), contains on the transmitting side an encoder (interleaver) encoding the data coming from the information source. From the encoder, according to commands from the power control unit in the down channels, the signals are fed to the multiplexer, where they are algebraically summed and fed to a modulator consisting of a spectrum expander and a multiplier controlled by the power control block in the up channels. Through the communication channel, the generated signal is fed to the receiving part, which contains a demodulator and a spectrum compression unit, which is connected by the corresponding outputs to the power control units in the down and up channels and to the decoder.

In this multi-access communication system, the method of generating and receiving signals does not provide sufficient noise immunity and the necessary reliability of communication with mobile users moving at high speeds (more than 150 km / h), since the determinism of Walsh codes does not allow the elimination of structural intentional interference and structural the secrecy of the signals, as well as the structure of the receiver itself, does not allow us to deal with frequency-selective fading of signals caused by the Doppler effect, which associated with these rates.

A new direction in the formation of broadband signals was the use of broadband chaotic signals, which have such useful properties compared to signals that use Walsh spreading codes, such as signal non-periodicity, a large volume of signal ensembles, better correlation properties, the ability to quickly synchronize, increased structural secrecy, the possibility of masking information.

A known system for transmitting discrete information with a continuous change of signal ensembles during operation, in which the formation of parallel M-positional orthogonal chaotic signals is carried out (see the article by M. B. Orlov, M. N. Chesnokov, M. M. Shipilov, A. I. . Scherbakov, “Synthesis of multi-frequency multi-position orthogonal chaotic signals,” Journal of Radio Engineering, No. 5, 2001, pp. 76-80).

и

, где k - номер сигнала. Выходы ФМКОП подключены к соответствующим входам селектора, в котором осуществляется расчет пикфактора сформированных многочастотных сигналов, их анализ и исключение сигналов с максимальным значением пикфактора. Далее с селектора отобранные сигналы поступают в блок выбора, где по заданному алгоритму производится выбор сформированных многочастотных сигналов в соответствии с n-разрядной комбинацией (M=2ⁿ). При этом устройство коммутации (УК), выходами связанное с соответствующими входами блока выбора, обеспечивает формирование сигнала на одном из M-выходов блока выбора в соответствии с указанной выше кодовой комбинацией в УК.This system contains in the transmitting part a chaotic sequence generator (GHP) that generates broadband chaotic signals in accordance with the original data stored in memory. These signals from the outputs of the GHC are fed to a shaper of modulated quadrature orthogonal sequences (FMKOP), where the procedure of orthogonalization of the signals is carried out, the result of which is to obtain a set of normalized vectors

and

where k is the signal number. The outputs of the FMCOP are connected to the corresponding inputs of the selector, which calculates the peak factor of the generated multi-frequency signals, analyzes them and excludes the signals with the maximum peak factor. Then, from the selector, the selected signals are sent to the selection block, where according to a given algorithm, the generated multi-frequency signals are selected in accordance with the n-bit combination (M = 2 ⁿ ). In this case, the switching device (CC), the outputs associated with the corresponding inputs of the selection block, provides a signal at one of the M-outputs of the selection block in accordance with the above code combination in the UK.

From the corresponding output of the selection block, the signal enters the combining device (UO), where also, to perform the synchronization procedure, the previously normalized vectors and a segment of the chaotic sequence are supplied to the corresponding inputs. From the output of the UO, the signals enter the modulator, where they are quadrature amplitude modulation. At the same time, when transmitting every n information bits, a new ensemble of parallel M-position orthogonal chaotic signals is formed (i.e., signals whose structure depends on the number of frequencies in the signal). Then, through the communication channel, the generated signals are fed to the demodulator of the receiving part. A demodulator in such a system usually contains a signal amplifier, a quadrature splitter, and an ADC coupled together. From the output of the demodulator, the demodulated signal is fed to a set of correlators and a synchronization device that performs the initial start of the GCP (receiving part), operating in accordance with the initial data stored in the memory. In the set of correlators, reference oscillations are used, which are generated, as in the transmitting part, using the FMCOP (receiving part), which enter the correlators through the selector (receiving part). The corresponding inputs of the FMCOP are connected to the corresponding outputs of the GC. From the outputs of the correlators, the signals are fed to a decision unit (RU), which forms a decision on the received information symbol, which is issued to the recipient of information.

This system, selected for the prototype, in comparison with the previous analogue, allows you to generate broadband chaotic signals that are not deterministic periodic signals, characterized by a large volume of signal ensembles, the best correlation properties.

However, in conditions of multipath interference in this system, it is not possible to ensure reliable reception of signals. Moreover, the system does not provide stable operation in case of discarding the frequency components, which reduces its noise immunity. In addition, the signals generated in the prototype do not allow a high degree of structural secrecy, in particular, due to the need to transmit the entire code sample to ensure synchronization of the system, which makes it possible to simulate a code sequence. The system also does not allow taking into account the Doppler effect in the communication channel and effectively eliminating it, which reduces reliable operation during the fast movement of subscribers (more than 150 km / h) due to frequency selective fading.

The technical result of the utility model is to increase noise immunity by providing reliable reception in the conditions of multipath interference and frequency selective fading, in particular, with the rapid movement of a mobile system subscriber, as well as increasing the structural secrecy of the generated signals.

The achievement of this result is achieved in a communication system using stochastic multi-frequency broadband coded radio signals, containing on the transmitting side a block for generating ensembles of signals of the transmitting side, including a generator of chaotic broadband coded signals, the input of which is connected to the output of the source data memory block, and its outputs are connected to the corresponding inputs shaper of quadrature (orthogonal) component signals, the outputs of which are connected to the corresponding the input inputs of the unit for evaluating and selecting signals, the outputs of which are the outputs of the unit for generating ensembles of signals and are connected to the corresponding inputs of the unit for selecting and storing signals, other corresponding inputs associated with the outputs of the switching device, the input of which is connected to the output of the information source, the outputs of the unit for selecting and storing signals connected to the corresponding inputs of the synchronization unit, the output of which is connected to the input of the modulator associated with the transmitting antenna, on the receiving side contains the first demodulator associated with the input to the receiving antenna, including a signal amplifier, ADC, and a quadrature splitter unit, the output of which is the output of the demodulator and connected to the input of the synchronization unit, corresponding to the output of the receiving side signal ensembles forming unit, including a generator of chaotic broadband encoded signals , the corresponding input of which is the input of the unit for generating ensembles of signals, another corresponding input of the generator x ical broadband encoded signals are connected to the corresponding output of the input side source data memory block, and the outputs of the chaotic broadband encoded signal generator are connected to the corresponding inputs of the quadrature (orthogonal) signal generator, whose outputs are connected to the corresponding inputs of the signal estimation and selection block, the outputs of which are outputs a block for generating ensembles of signals of the receiving side, a decision block, the output of which is the output for connecting to the consumer information, characterized in that the chaotic broadband encoded signal generator on the transmitting and receiving sides comprises a serially connected controlled clock generator, a linear recursive register and a nonlinear feedback device, while the corresponding input of a controlled clock generator is connected to the output of the source memory block data respectively of the transmitting and receiving sides, to the connection point of the controlled clock and linear output of the recursive register, the output of the nonlinear feedback device is connected, the corresponding input of which is connected to the corresponding output of the source data memory block, respectively, of the transmitting and receiving sides, the other corresponding output of which is connected to the corresponding input of the linear recursive register, respectively, of the transmitting and receiving sides, and its corresponding output is connected to the corresponding input of the nonlinear feedback device of the transmitting and receiving sides, respectively, is the output m of a chaotic broadband encoded signal generator for connecting to the corresponding input of the quadrature component shaper of the signal, respectively, of the transmitting and receiving sides, the other input of which is connected to the corresponding output of the source data memory block on the transmitting and receiving sides, respectively, and the other corresponding input of the controlled clock generator is connected to the corresponding output block evaluation and selection of signals, and on the receiving side introduced block evaluation discrete parameter , a signal delay unit and a filtering unit for continuous parameters, while the input of the signal delay unit and the corresponding input of the discrete parameter estimator are connected to the input of the synchronization unit, the output of the signal delay unit is connected to the corresponding input of the continuous parameter filtering unit, the other corresponding inputs of which are connected respectively to the corresponding the output of the decision block and the corresponding output of the block for generating the ensemble of signals, which is the output of the signal estimation and selection block fishing, and the output parameters of continuous filtration unit connected to the other respective input of a discrete parameter estimation unit, wherein the input signal generation unit assemblies at the receiving end for connecting to the output synchronization unit is controlled oscillator input clock generator of chaotic broadband encoded signals.

The achievement of the technical result, in contrast to the prototype, is provided in the proposed technical solution by generating fundamentally new parallel-serial encoded signals that have stealth and can protect information. This is due to the fact that the generated signals:

- have a larger base volume, which increases noise immunity and the speed of information transfer;

- have better correlation properties, which gives a greater gain in conditions of multipath interference when receiving signals;

- more resistant to discarding the frequency components than parallel signals in the prototype, which accordingly provides a gain in noise immunity;

- have a greater degree of structural secrecy than conventional broadband stochastic signals (SHX) in the prototype, which is explained by the properties of registers with non-linear feedback functions (in blocks of a linear recursive register (LRR) and a non-linear feedback device (NLOS) in conjunction with a controlled clock generator ), therefore, they are well protected from listening;

- due to the recurrence of M-sequences (LRR and NLOS blocks), it is possible to transmit not the entire code sample (for synchronization), but part of it, which significantly reduces the probability of its interception and greatly complicates the possibility of simulating a code sequence, i.e. the signal is well protected from the effects of intentional jamming interference.

In the receiving part, the received mixture passes through the signal amplifier (US), the ADC and the block of quadrature splitters, resulting in the formation of the received samples of the quadrature components of the signal (KSS) (hereinafter referred to as POKSS).

The signal delay unit (BSS) carries out the delay of the POKSS for a time equal to τ _m + T, where τ _m is the multipath interval, and T is the duration of the clock interval. The delay in the path containing the filtering block of continuous parameters is necessary to remove the manipulation of the received signal. It can be provided after a decision is made in the unit for evaluating discrete parameters (BODP). Due to the presence of multipath, to remove manipulation from the signal, it is necessary to memorize the previous solution for the time interval τ _m + T> T. It is carried out in the decision block (BDP). In turn, this block uses the parameter estimates obtained at the previous clock interval, which is permissible with a slow change in parameters.

After delays for a time of τ _m + T, these quadrature components are fed to L continuous parameter filtering units (BPSF), where continuous parameters are filtered and clock synchronization is performed. When filtering the parameters, the previous solutions from the BPR on the multipath interval are used.

The discrete parameter estimation unit (BODP) operates using quadrature signal components and estimates of signal parameters in all beams. It implements the summation of the energies of all the rays of the multipath signal.

The synchronization unit (BS) synchronizes the received signals in cycles and cycles, the signal ensemble formation unit (BFAS) and the signal delay unit (BSS) serve to simultaneously generate ensembles of chaotic signals on the transmitting and receiving sides. The algorithm for generating ensembles of signals in BFAS at transmission and reception is the same, and differs from the prototype in that it allows you to receive a signal under the influence of the Doppler effect, multipath interference, and frequency-selective fading.

The proposed utility model is illustrated by drawings, in which Fig. 1 shows a block diagram of the proposed device, Fig. 2 is a block diagram of a transmitting part operation algorithm, Figs. 3a and b are a block diagram of a receiving part operation algorithm, and Fig. 4 - a functional diagram of the formation of code sequences in the blocks of the NOOS and LRR in both the transmitting and receiving parts.

According to figure 1, a communication system using stochastic multifrequency broadband encoded radio signals contains on the transmitting side a block 1 for generating ensembles of signals of the transmitting part (BFAS), which includes a generator 2 of chaotic broadband encoded signals, consisting of a controlled clock generator 3 (UHF), linear recurrence register 4 (LRR) and non-linear feedback device 5 (NLOS), block 6 of the source data memory (BPID), shaper 7 quadrature component signals (FCSS) and 8 lok evaluation and selection signals (BOiSS). In addition, on the transmitting side there is a block 9 for selecting and storing signals (BViZS), a device 10 for switching signals (CC), a block 11 for synchronizing the transmitting part (BS) and a modulator 12 connected by the output to the transmitting antenna 13. At the same time, there are 2 chaotic oscillators in the generator broadband encoded signals, the corresponding inputs of UHFM 3 are connected to the corresponding outputs of BPID 6 and BOISS 8, and the output of UHFM 3 is connected to the output of the NOOS 5 and the corresponding input of LRR 4, the other input of which is connected to the corresponding output of BPS 6 and the corresponding outputs of LRR 4 connected to the corresponding inputs of the NOOS 5 and FCCS 7, the other input of which is connected to the corresponding output of the BPID 6, the outputs of the FCCS 7 are connected to the corresponding inputs of the BOISS 8, the other corresponding input of which is connected to the corresponding output of the BPID 6. The outputs of the BIOSS 8, which are the outputs of the chaotic generator 2 broadband encoded signals are connected to the corresponding inputs of BViZS 9, to the other corresponding inputs of which are connected the corresponding outputs of UKS 10, to the input of which a signal is supplied from the information source. The corresponding outputs BViZS 9 are connected to the corresponding inputs of the BS 11, the output of which is connected to the input of the modulator 12, connected to the output of the transmitting antenna 13.

On the receiving side, the system contains a receiving antenna 14 connected to the input of the demodulator 15, which is the input of the signal amplifier (US) 16 entering it, the output connected to the input of the ADC block 17, the output connected to the input of the quadrature splitters (BKR) block 18, the output of which is the output of the demodulator 15, which is connected to the inputs of the receiver synchronization unit (BS) 19, the signal delay unit (BSS) 20 and the discrete parameter estimator (BOD) 21, the output of which is connected to the corresponding input of the decision block 22 (BPR), one output of which is connected to the corresponding input of the continuous parameter filtering unit 23 (BFNP), and the other output of the BDP 22 is a signal output for the information consumer. The output of BS 19 is connected to the input of BFAS 24, which is the corresponding input of the generator 25 of chaotic broadband encoded signals of the receiving part, which is the input of the input UGTCH 26, the output of which is connected to the corresponding input of the LRR 27 and the output of the NOOS 28, the corresponding input of which is connected to the output LRR 27, is the output of the generator 25 chaotic broadband encoded signals, which is connected to one of the inputs of the FCCS 29 of the receiving part, the outputs associated with the first and second corresponding inputs of the BOISS 30 the receiving part, the third corresponding input of which is connected to the corresponding output of the BPID 31 of the receiving part, the other corresponding outputs of which are connected to the corresponding inputs of UGTCH 26, LRR 27, NUOS 28 and FKSS 29, and the corresponding input of UGTCH 26 is connected to the corresponding output of BOISS 30, other corresponding the outputs of which are connected to the corresponding inputs of the BDP 22 and BFNP 23.

The work of the proposed system is carried out in accordance with figure 1, figure 2, figure 3 as follows.

, M - объем ансамбля:Consider the general view of the parallel-serial signal S _k (t) generated in BFAS 1 from the ensemble {S _k (t)},

, M is the volume of the ensemble:

; g[t-(j-1)t_u] - стробирующая функция, определяемая соотношением:for (q-1) T≤t≤qT, where q is the number of the clock interval of the TI, T is the duration of the TI, i is the number of the frequency component ω _i in the signal (i = 1 ... m); m is their number; j is the number of the signal subelement (j = 1 ... l); l is the number of subelements of duration

; g [t- (j-1) t _u ] is the gating function defined by the relation:

Consider the operation of BFAS 1 and the signal formation process in more detail.

UGTCH 3 is a meander generator and sets the clock frequency for operation of the LRR 4, thereby setting the initial mode of its operation. NOOS 5 is a logical device that forms the feedback of the register so that at its output we have a sequence of samples, which is an M-sequence. SPLM 5 consists of modulo 2 adders and multipliers, the number and circuitry of which are selected so that at the output of LRR 4 a non-periodic sequence of maximum length equal to 2 ^{m-1 is} generated, where m is the number of triggers in LRR 4.

, a m - количество триггеров, из которых состоит регистр, которое задается в блоке 6 памяти исходных данных.Thus, at the output of LRR 4, we have samples of digital sequences, which we denote respectively: x _i , y _i , where

, am - the number of triggers that make up the register, which is set in block 6 of the source data memory.

The resulting digital M-sequences are fed to the FCCS 7, which performs:

1. the formation of quadrature component signals (KSS) according to the ratios:

2. orthogonalization and normalization of the CSS according to the formulas:

- норма k-го сигнала.where k = (1 ... M),

is the norm of the kth signal.

,

формируются согласно соотношениям:Here, the orthogonal and normalized quadrature components of the signal (KSS)

,

are formed according to the ratios:

, а

Where

, but

, входящие в (5), равны:where (ν _k w _r ) is the scalar product of the signals ν _k and w _r . Quantities

included in (5) are equal to:

равенThe square of the norm of the rth signal

is equal to

Further, the orthogonal and normalized KSS arrive at BOISS 8, where the assessment of the non-orthogonality of the KSS takes place and if the acceptable value of the non-orthogonality (DZN) is not reached, then items 1 and 2 are repeated until the DZN is reached. Together with the assessment, the selection of KSS by the given value of the peak factor occurs. Those. calculating the peak factor and comparing it with a valid value from block 6 of the source data memory. KSS that do not satisfy the given peak factor are discarded.

Then, the orthogonal and normalized SSCs, satisfying the given peak factor, are fed to BViZS 9. Here, the quadrature components of the signal are selected in accordance with the AI. Each bit of information in block BViZS 9 is encoded by one signal and using UK 10 the signal corresponding to this bit is selected in BViZS 9. Next, the digital signals (which are presented as KSS) are converted into analog ones, followed by quadrature-amplitude modulation in modulator 12 Analytically received signal can be recorded according to formula 1.

Block 6 of the source data memory for generating signals sets the length of the LRR - the number of triggers or cells that store 1 bit of information, the structure of the NOOS 5, i.e. the required number and method of circuitry connecting the logic gates of NOOS 5 and the triggers of the LRR 4 to each other, the permissible value of non-orthogonality for the FCCS 7, the set value of the peak factor and the number of signals in the ensemble for BIOSS 9. The synchronization block of the transmitting part (BS) synchronizes the received signals by clock cycles and cycles.

In the receiving part, the received mixture passes through the US 16, BKR 17 and ADC 18, as a result of which the received KSS samples are formed (hereinafter referred to as POKSS).

The received rth version of the signal in discrete time will be equal to

moreover:

Here U and V are the quadrature components of the received mixture. Equations for quadrature components of the channel transfer coefficient at the i-th frequency

Here, α determines the width of the fluctuation spectrum, σ ² is the CS dispersion, n _1ik (l), n _1ik (l) are mutually uncorrelated for different i, k, l Gaussian random variables with zero mean and unit dispersion.

B (11) λ _1i0 (l), λ _1i0 (l) are the constant known values of the CS.

The CS of the received signal in the form of relations (11), (12) corresponds to the Rice model of independently fading signals at the ith frequency. In the absence of regular components, the Rayleigh channel model follows from it.

Note that the adopted model, of course, is somewhat idealized, because does not take into account the correlation of fading on different subcarriers.

The recurrent stochastic equations for the initial phase on the ith subcarrier are as follows

The equations describing the parameters of the random delay of the boundaries of the signal elements are as follows

- мощность этих флуктуаций.Here Ω _k is a random component of the instability of the clock frequency; Δ = h is the sampling interval; γ _Ω determines the width of the fluctuation spectrum of the clock frequency;

is the power of these fluctuations.

The models described above were used in the statistical synthesis of the multifunctional algorithm for demodulation and synchronization of complex multi-frequency BSSs. The synthesis was carried out on the basis of the Markov processes filtering algorithm. It was supplemented by relations describing the synchronization of the received signal along the boundaries of complex multi-frequency BSS. We will call this type of synchronization the delay synchronization of complex multi-frequency BSSs.

The main properties of the algorithm:

- from it, as a result of simplifications and assumptions, a number of simpler algorithms can be obtained from which one suitable for implementation can be selected;

- on the basis of this algorithm, simpler reception algorithms can be obtained than the reception algorithms that are optimal for the conditions of exposure to white Gaussian noise, but at the same time provide suppression by concentrated comb-type noise and pulsed noise.

Here is a simplified algorithm derived from the optimal algorithm. Its features are:

1. the application of feedback on the solution, i.e. estimation of the signal and channel parameters is carried out as a result of processing the delayed implementation of the received mixture after deciding on the transmitted signal;

2. The use of constant amplification factors during recurrent filtering of parameters.

The algorithm includes the following system of interconnected recurrence relations, written below.

1. The filtering equations of the quadrature components of the complex channel transfer coefficient on the subcarrier with number i (i = 1, 2, ..., m):

2. The equations for filtering the phases of the i-th subcarriers:

3. The equations for filtering the parameters of the time delay of the boundaries of the clock intervals:

The value of D _{k + 1} included in this expression is calculated as follows:

4. The relations describing the signal search process (synchronization by the time delay of complex multi-frequency SHPS) have the form:

but)

for ν = 1, ..., N, where N is the total number of delay points of uncertainty;

b)

where ν _max is the point of the zone of uncertainty corresponding to the maximum value of z _ν ;

, входящая в выражение (20), равна:c) statistics

included in expression (20) is equal to:

5. Ratios for deciding on the number of the received signal:

, входящие в (26), вычисляются следующим образом:(according to this expression, a decision is made to receive a signal with number r if the system of inequalities (26) holds, and moreover, r, p = 1, 2, ..., M and r. p. Values

included in (26) are calculated as follows:

where ν _max is the point of the zone of uncertainty, determined after synchronization by the delay of complex multi-frequency BBA according to the relations No. (20), (21). Note that everywhere in the above relations the values of d, which determines the number of the time interval, depend on the number of the point of the uncertainty zone ν. When determining the true time interval (after synchronization by the delay of complex multi-frequency BBA) ν = ν _max .

The block diagram of a multifunctional algorithm for demodulation and synchronization of complex multi-frequency NPS is shown in Fig.3.

The receiver contains m quadrature splitters with discretizers to calculate the samples of the quadrature components of the received mixture. The clock synchronization block (BS) implements relations (18), (19). In filtering blocks of continuous parameters (BFNP), the channel parameters are filtered according to relations (15) - (17). The discrete parameter estimation unit (BODP) and the decision-making and decision unit (BDP) implement relations (20) - (27).

Let us explain the principle of operation of the demodulation algorithm - synchronization. Let us first consider the case when the delay synchronization of complex multi-frequency NPS is established, that is, the time boundaries of the received complex multi-frequency NPS coincide with the corresponding boundaries of the reference signals.

The receiver belongs to the class of receivers with feedback on the decision. Samples of the quadrature components of the received mixture arrive at the BFNP with a delay for the duration of the signal element T. In the BODP, a decision on the signal element is made at the end of the signal element. Therefore, the BFNP simultaneously receives the readings of the quadrature components and decisions with the BODP. As a result, manipulation is removed in the BFNP, and the parameters are estimated by the demodulated signal.

Initially, due to the fact that parameter estimates are formed incorrectly, the BODP also generates random decisions about the received signal. At some point in time, random decisions about the discrete parameter of the signal coincide with the correct decision. In this case, the BFNP begins to formulate estimates of the quadrature components of the channel transfer coefficient close to true. This increases the frequency of correct decisions about a discrete parameter, which, due to the correct removal of manipulation, increases the accuracy of the estimates obtained. The result is synchronism.

Let us now consider the case of establishing synchronization for the delay of complex multi-frequency BSSs. To simplify the explanation, we first assume that the estimates of the signal parameters are true. To carry out delay synchronization with complex multi-frequency BSSs, the correlation integrals are calculated (as in decision making) according to expressions (22) - (25) and the maximum value for all possible signal variants is determined according to expression (20). Note that in the presence of synchronization by the delay of complex multi-frequency NPS, this value is more likely to appear at the output of the branch, the number of which corresponds to or equal to the number of the received signal.

Then, according to expression (20), the value is calculated for all points of the uncertainty zone by delay, and among them, according to relation (21), the point of the uncertainty zone corresponding to the maximum value of z _{ν is} determined. At the same time, the search process for the delay of complex multifrequency SHPS ends.

We now take into account the procedure for estimating channel parameters. In this case, the process of entering synchronism differs only in that the processing time increases at each point in the zone of uncertainty by the interval allotted for the completion of transient processes when filtering parameters.

BSS 20 carries out a delay of POCSS for a time equal to τ _m + T, where τ _m is the multipath interval, and T is the duration of the clock interval. The delay in the path containing the BFNP 23 is necessary to remove the manipulation of the received signal. It can be provided after a decision is made in the BODI 21. Due to the presence of multipath, in order to remove manipulation from a signal, it is necessary to memorize the previous solution for the time interval τ _m + T> T. It is carried out in BDP 22. In turn, this block uses the parameter estimates obtained at the previous clock interval, which is permissible with a slow change in parameters.

After delays for a time τ _m + T, these quadrature components are fed to L continuous parameter filtering units (BFNP 23), where continuous parameters are filtered and clock synchronization is performed. When filtering the parameters, the previous solutions from BDP 22 on the multipath interval are used.

BODP 21 operates using quadrature signal components and estimates of signal parameters in all beams. It implements the summation of the energies of all the rays of the multipath signal

BFAS 1 and 24 on the transmitting and receiving sides, respectively, serve to simultaneously generate ensembles of chaotic signals on the transmitting and receiving sides. The algorithm for generating ensembles of signals in BFAS 1 and 24 on transmission and reception is the same.

An example of the execution of the blocks of the device can be explained as follows.

Name on the scheme Chip Link Source data memory block M29W256GH http://cataloq.qaw.ru/index.php?page=component_detail&id=30131 UHTCH TMS C6455, _Instruments / micros / dsp / c6000 / 320c64x / TMS320C6455.htm Shaper KSS BOISS Altera MAX 5 BViZS mponent_detail & id = 56307 UK AD420 BS M mponents_list & id = 55 CSS TMS C6455, http://www.qaw.ru/html.cqi/txt/ic/Texqs_Instruments/micros/dsp/c6000/320c64x/TMS320C6455.htm Block quadrature splitters Altera MAX 5 BS mponent_detail & id = 56307 BODP AD10200 Bdr BZS http://cataloq.qqw.ru/index.php?page=components list & id = 30 BFNP

The software implementation of the proposed system is illustrated by flowcharts of the operating algorithms of the transmitting, receiving parts of the device, as well as the functional diagram of its operation, shown in figure 2, figure 3 and figure 4, respectively.

Claims (1)

A communication system using stochastic multifrequency broadband encoded signals, comprising, on the transmitting side, a unit for generating ensembles of signals of the transmitting side, including a generator of chaotic broadband encoded signals, the input of which is connected to the output of the source data memory unit, and its outputs are connected to the corresponding inputs of the quadrature (orthogonal) generator component signals, the outputs of which are connected to the corresponding inputs of the unit for evaluating and selecting signals, the outputs of the cat They are the outputs of the block for generating ensembles of signals and are connected to the corresponding inputs of the block for selecting and storing signals, other corresponding inputs for the outputs of the switching device, the input of which is connected to the output of the information source, the outputs of the block for selecting and storing signals are connected to the corresponding inputs of the synchronization block, the output of which connected to the input of the modulator associated with the transmitting antenna, on the receiving side containing a demodulator connected to the input of the receiving antenna with the demodulator, including the signal amplifier, ADC and the quadrature splitter unit, connected in series, the output of which is the output of the demodulator and connected to the input of the synchronization unit, corresponding to the output of the receiving side signal ensembles forming unit, including a generator of chaotic broadband encoded signals, the corresponding input of which is the input of the formation unit ensembles of signals, another corresponding input of the generator of chaotic broadband encoded signals is connected the corresponding output of the source side data source memory block, and the outputs of the chaotic broadband encoded signal generator are connected to the corresponding inputs of the quadrature (orthogonal) component signal generator, the outputs of which are connected to the corresponding inputs of the signal estimation and selection block, the outputs of which are the outputs of the receiver side signal ensemble generation unit , a decision block, the output of which is an output for connecting information to a consumer, characterized in that the generator of chaotic broadband encoded signals on the transmitting and receiving sides contains a serially connected controlled clock generator, a linear recursive register and a nonlinear feedback device, while the corresponding input of a controlled clock generator is connected to the output of the source data memory block of the transmitting and receiving sides, respectively, to the connection point of a controlled clock generator and a linear recursive register is connected to a nonlinear output feedback device, the corresponding input of which is connected to the corresponding output of the source data memory block, respectively, of the transmitting and receiving sides, the other corresponding output of which is connected to the corresponding input of the linear recurrence register, respectively, of the transmitting receiving sides, and its corresponding output is connected to the corresponding input of the nonlinear feedback device, respectively transmitting and receiving sides and is the output of a generator of chaotic broadband encoded signals signals for connecting to the corresponding input of the quadrature component of the signal, respectively, of the transmitting and receiving sides, the other input of which is connected to the corresponding output of the source data memory block, respectively, on the transmitting and receiving sides, the other corresponding input of the controlled clock generator is connected to the corresponding output of the signal estimation and selection unit and on the receiving side a discrete parameter estimator, a signal delay unit, and a continuous vapor filtering unit are introduced meters, while the input of the signal delay block and the corresponding input of the discrete parameter estimator are connected to the input of the synchronization block, the output of the signal delay block is connected to the corresponding input of the continuous parameter filtering block, the other corresponding inputs of which are connected to the corresponding output of the decision block and the corresponding output of the block the formation of the ensemble of signals, which is the output of the unit for evaluating and selecting signals, and the output of the filtering unit of continuous parameters li ne corresponding to another entry discrete parameter estimation unit, wherein the input signal generation unit assemblies at the receiving end for connecting to the output synchronization unit is controlled oscillator input clock generator of chaotic broadband encoded signals.

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