RU2720215C1 - Method of protecting narrow-band radio communication systems in conditions of complex radioelectronic situation and set of means for realizing said method - Google Patents

Abstract

FIELD: radio engineering and communications.

SUBSTANCE: invention relates to radio communication and specifically to systems for protecting narrow-band radio communication systems in conditions of complex radioelectronic environment caused by interference of both internal and external interference. For this purpose, on the transmitting side of the system, a code FM signal generator is included, which includes a generator of initial FM signals and a summator of the FM signals, and an analogue-to-digital signal converter is introduced on the receiving side, a signal scale converter for time compression of a PM packet of a video signal of a message, a device for compensation of pulse interference, an interpolation device, an amplitude-normalizing device, a decoder with correlation processing of FM signaling signals, a generator of initial FM signals of the receiving side and an adder of discrete signals.

EFFECT: reduced effect of multibeam radio signals in narrow-band radio communication systems under conditions of complex radioelectronic environment and simultaneously high noise-immunity of the radio communication system from interference due to high signal-to-noise ratio when using OCDM technology at one carrier frequency.

2 cl, 14 dwg

Description

The invention relates to the field of radio communications, and in particular, to protection systems for narrow-band radio communication systems in a complex electronic environment due to the influence of both intra-system and external interference (multipath propagation, concentrated and pulsed interference, fast and slow fading, and others).

The DKMV radio communication systems (3-30 MHz) are characterized by the arrival of signals to the receiving side by multiple reflection from the ionosphere and the earth's surface, therefore, at the receiving point, the resulting signal is a superposition of many signals with different amplitudes and initial phases. This causes interference within the transmitted character or intersymbol interference [1-8].

Known methods of combating multipath signals and interference in radio communication systems, among which are frequency hopping, compensation of radio signals of additional beams, reception on antennas spaced apart in space, use of a guard interval, frequency division multiplexing method, etc. [1-8].

The disadvantages of the above methods are the deterioration of the noise immunity of the radio communication system while complicating the jamming environment, the need to use several carrier frequencies, as well as the small delay range of the radio signals of the second and other rays relative to the first beam, which ensures reliable transmission of information.

The theory of the formation and reception of signal-code structures in general is a fairly new and modern field of communication theory. The synthesis of signal-code constructions is not reduced to a separate and independent choice of code and modulation method, but is performed as a whole, taking into account the interconnectedness of these procedures. The reception of signal-code constructions is carried out exclusively, as the reception of the entire signal-code block, and provides a significant increase in the reliability of data transmission in radio communication systems [9-12].

It should be noted that at present, the development of hardware and software on the RDS platform (programmable radio) has expanded the possibilities of solving this problem using promising and rapidly developing areas of signal-code constructions (CCM) on the following technologies, depending on the purpose of using radio communication systems [9 -14]:

- OFDM signals with pseudo-random tuning of the operating frequency, which is widely used in narrow-band DKMV radio communication systems;

- CDMA signals with direct expansion of the spectrum, which is widely used in broadband radio and wire communication systems;

- OCDM signals with orthogonal code division of channels, which is used in broadband radio communication systems and provides its high noise immunity.

In [11], the results of simulation of the error probability for signal-code constructions using OCDM and OFDMA technologies are presented, from which it follows that the use of OCDM technology in broadband radio communication systems provides noise immunity much higher than OFDM, but is inferior in terms of transmission rate data.

It should be borne in mind that in broadband radio communication systems, for example, FM signals with a large base B are used, which is determined by the product of the spectrum width of the signal F by the signal duration T [6]

where T is the duration of the signal;

F is the signal spectrum width.

Currently, there is no information on the use of OCDM signal technology in narrow-band DKMV radio communication systems, therefore, if there are not only multipath radio signals in the communication channel, but also when the interference situation is complicated, the frequency and energy resources are limited, the implementation of OCDM technology in narrow-band DKMV radio communication systems bandwidth is relevant.

In the engineering plan, these are the tasks of implementing the obtained transformation algorithms taking into account the acceptable complexity and speed of the processors, transmitter and receiver, as well as improving operational parameters.

The closest analogue of the claimed invention is a guard interval method for reducing the influence of multipath radio signals in narrow-band radio communication systems, taken as a prototype. The essence of this method lies in the fact that the radio signals are sent from the transmitter not in a continuous stream, but intermittently, in order to provide a guard interval before each character to eliminate intersymbol distortions [1].

To implement the method of the protective interval, the transmitting device contains a series-connected message source, a shaper of discrete message signals with protective intervals in front of them, an encoder, a phase shaper, a phase modulator, a power amplifier and a transmitting antenna, and the receiving device contains a series-connected receiving antenna, a microwave amplifier , a phase demodulator, a decisive threshold device, the second input of which is connected to the output of the threshold shaper, and the output of the decisive threshold device roystva connected to the input of the converter digital communications signals.

The essence of the guard interval method is that to ensure the reception of signals, as in a channel with general fading (lack of multipath signals), it is necessary to provide a longer duration of the emitted radio signals of messages, compared with the duration of the maximum delay time between multipath signals [1].

The advantages of the guard interval method are its rather simple implementation, the ability to work on one carrier frequency in conjunction with other methods of protecting narrowband data transmission channels.

The main disadvantage of the guard interval method is the dependence of its effectiveness in terms of reducing the influence of multipath signals on the duration of the emitted radio signals, since with an increase in their duration, the information transfer rate is significantly reduced, the energy performance and throughput of the data transmission channel are degraded, and the noise immunity of the radio communication system is worsened when complicated interference environment.

The main technical problem to be solved by the claimed invention is directed to reducing the influence of multipath radio signals in narrow-band radio communication systems in a complex electronic environment and at the same time increasing the noise immunity of a radio communication system from interference by increasing the signal-to-noise ratio when using OCDM technology on a single carrier frequency.

The specified technical result is achieved by the fact that in the method of protecting narrow-band radio communication systems in a complex electronic environment, including on the transmitting side of the radio communication system the operation of generating messages, generating discrete signals, encoding discrete signals, phase formation, phase modulation, amplification of radio signals and radiation of radio signals by a transmitting antenna and, on the receiving side, including the operation of receiving radio signals with a receiving antenna, amplification of microwave signals, phase demodule In order to form, generate a threshold signal, solve the threshold allocation of signals according to the likelihood criterion and convert discrete message signals to a consumer-friendly form, the operations of generating M = 4 initial FM signals, summing M = 4 initial FM signals to form of N = 4 discrete binary signals of the code FM signal in the form of a parallel assembly package containing information about M = 4 source FM signals, and on the receiving side after the operation, phase d modulation additionally introduced the operations of analog - digital signal conversion, signal scale conversion, impulse noise compensation, interpolation conversion to restore the received phase information signals, normalize the amplitude of the FM message signal, M = 4 channel correlation processing of the FM message signals containing information about M = 4 source FM signals, the formation of M = 4 source FM signals for M = 4 channel correlation processing, the summation of discrete signals with M = 4 channel corre Relational processing to provide a solution to the threshold allocation of message signals according to the likelihood criterion.

The specified technical result is achieved by the fact that the complex of means of protection of narrow-band systems in complex radio-electronic conditions, containing on the transmitting side of the radio communication system a series-connected message source, a shaper of discrete signals, an encoder, a phase shaper, a phase modulator, a power amplifier and a transmitting antenna, and the receiving side comprising a receiving antenna, a microwave amplifier and a phase demodulator, as well as a shaper connected in series A gate, a decisive threshold device and a converter of discrete message signals, from the output of which information is supplied to consumers, on the transmitting side of the radio communication system, an additional shaper of the initial FM signals of the transmitting side is introduced, the outputs of which are connected to the corresponding inputs of the adder of the initial FM signals, the outputs of the adder of the initial FM signals are connected to the corresponding inputs of the encoder, and on the receiving side of the radio communication system, an additional shaper of the initial FM signals of the receiving station is additionally introduced Rones connected in series by an analog-to-digital signal converter, signal scale converter for compressing the time packet of the FM video message signal, an impulse noise compensation device, an interpolation device, an amplitude normalizing device and a decoder with correlation processing of the FM signal signals whose outputs are connected to the corresponding inputs discrete signal adder, the output of the adder of discrete signals is connected to the second input of the decisive threshold device, the outputs are formed I starting FM signals of the receiving side are connected to respective inputs of a decoder with correlation processing FM communication signals, wherein the input analog - digital converter connected to the output signal of the phase demodulator.

On the transmitting side of the radio communication system, an additional code FM signal shaper is introduced, including an initial FM signal shaper and an FM signal adder. As M = 4 source FM signals, orthogonal elements of the derivative system of N = 4 order signals with small side lobes of the autocorrelation function are formed by adding modulo 2 orthogonal Walsh codes N = 4 order and an N = 4 Barker code whose autocorrelation function has small side petals [14, 15].

As a result of combining in time and summing M = 4 the initial FM signals, the total FM signal is formed in the form of a parallel assembly packet of N = 4 discrete binary signals with the same amplitudes 0 or -2, from which the code FM signal is formed in the form of N = 4 discrete binary signals with the same amplitudes 1 or -1 (phases 0 or π).

The encoder modulates with a code FM signal each discrete binary message signal, as a result, each discrete message signal takes the form of a packet of code FM signal containing information on M = 4 orthogonal source FM signals, which can be transmitted and received using phase 2 modulation and demodulation -FM, which increases the reliability of data transmission.

At the receiving side of the radio communication system, at the output of the 2-FM phase demodulator, an additional computing communication module (Navy) is introduced based on a software-defined hardware platform using SDR technology (programmable radio), which provides:

- analog - digital signal conversion;

- conversion of the signal scale for time compression of the FM packet of the video signal of the message, which reduces the time of its conversion and processing in the computing communication module;

- elimination at the output of the phase demodulator of a single error in the phase information arising from impulse noise by compensating (or reducing the level) of the impulse noise and using an interpolation device to restore phase information from neighboring samples of the message video signal;

- normalization of the amplitude of the FM signal of the message according to the level of the original FM signals, which are used as reference signals in correlation processing;

- M = 4 channel correlation processing of the FM message signal containing information about M = 4 orthogonal source FM signals with a base of B = 4, which provides an increase in the signal-to-noise ratio in each channel by N = 4 times (6 dB);

- summation of the results with M = 4 channels of the correlation processing of the FM signal of the message, which provides an additional increase in the signal-to-noise ratio by M = 4 times (6 dB);

- selection of discrete message signals using a decisive threshold device according to the likelihood criterion;

- conversion of discrete message signals to the form necessary for the user.

In FIG. 1 shows a structural diagram of a radio communication system, where it is indicated:

1 - message source;

2 - shaper of discrete signals;

3 - encoder;

4 - former source FM signals of the transmitting side;

5 - adder of the initial FM signals;

6 - phase shaper;

7 - phase modulator;

8 - power amplifier;

9 - transmitting antenna;

10 - receiving antenna;

11 - microwave amplifier;

12 - phase demodulator;

13 - analog - digital signal converter;

14 - signal scale converter;

15 - device compensation impulse noise;

16 - interpolation device;

17 - amplitude normalizing device;

18 - decoder with correlation processing;

19 - former source FM signals of the receiving side;

20 - adder of discrete signals;

21 - decisive threshold device;

22 - threshold shaper;

23 - Converter discrete signal messages.

Blocks that are standard for radio communication systems (such as power supplies, clocks, etc.), in FIG. 1 are not shown.

It should be noted that when describing the operation of a set of security features, simulation results in the MathCAD environment are given, which are illustrated by the figures:

- in FIG. 2, FIG. 4 - FIG. 10 on the vertical axes the amplitudes of the signals are indicated in relative units relative to the amplitude of the discrete binary signal, and on the horizontal axes the delay values τ of the signal are indicated in relative units of the symbol duration t / τ _and ;

- in FIG. 3, FIG. 11-14 on the vertical axes the amplitudes of the signals are indicated in relative units relative to the amplitude of the discrete binary signal, and on the horizontal axes the time is indicated in relative units of the symbol duration t / τ _and .

A set of remedies works as follows.

On the transmitting side of the radio communication system, the message is generated in message source 1, for example, as a text message from a sequence of letters of the alphabet, each of which is encoded by a specific sequence of numbers 0 and 1.

In the shaper of discrete signals 2, text messages are converted into a sequence of discrete signals with an amplitude of 0 and 1, which is fed to the first input of the encoder 3, the second input of which receives a code FM signal from a code shaper FM signal, consisting of a source shaper FM signal 4 and the source adder FM signals 5.

Let us consider in more detail the formation of a code FM signal. The initial FM signals are formed in the form of orthogonal elements of the derived signal system, the autocorrelation function of which has small side lobes, by multiplying (summing modulo 2) element-wise phase-shifted Walsh codes with orthogonality properties and a Barker code with an autocorrelation function (ACF) with small side lobes, and are defined as

) - m -й элемент кода Уолша;where wal (m,

) is the mth element of the Walsh code;

m = 1, 2, 3, ..., M;

M is the number of Walsh code elements;

= {0, π} - фазы элементов кода Уолша;

= {0, π} are the phases of the elements of the Walsh code;

b _n is the n-th element of the Barker code;

n = 1, 2, 3, ..., N;

N is the number of elements of the Barker code.

As base codes, M = 4 Walsh codes and a Barker code of N = 4 orders were selected; as a result of summing them modulo 2, the elements of the derived system of N = 4 order signals have the form [15, 16]:

From the above elements of the derived signal system defined by relation (3), it follows that the number M = 4 Walsh codes determines the number of elements x _n (t) of the derived signal system, and the number of elements N = 4 of the Barker code determines the number of symbols of elements x _n (t ) derived signal system.

Taking into account the phases, the initial FM signals in the form of elements x _n (t) of the derived signal system (3) are converted to:

In FIG. Figure 2 shows the initial FM signals in the form of elements y _n (t) of the derived signal system, defined by relation (3).

It should be noted that the width of the spectrum of the elements of the derived signal system (4) is determined by the convolution of the spectra:

where S ₁ (ω), S ₂ (ω) is the width of the spectrum of the Walsh and Barker codes, respectively, and will be approximately determined by the duration of one discrete element of the Barker code.

In FIG. Figure 3 shows the ACF of the initial FM signals in the form of elements of a derivative system of sequence signals (4).

As follows from the given ACF, M = 4 source FM signals of duration τ _and at N = 4 the side lobes of the ACF do not exceed the level of 0.25 from the main lobe and are in antiphase, which allows the side lobes to be eliminated when summing the ACF M = 4 of the initial FM signals.

In FIG. Figure 4 shows the total ACF M = 4 of the initial FM signals in the form of elements of a derivative system of signal sequences (3).

In the adder of the initial FM signals 5, the time is combined and the summation M = 4 of the initial FM signals at N = 4, determined by the relation (4). As a result of this, a package of parallel assembly of N = 4 discrete signals with amplitudes equal to -2 or 0 is formed, from which a packet of a code FM signal with amplitudes equal to -1 or 1 is formed.

In FIG. 5 shows the formation of a package of code FM signal with amplitudes equal to -1 or 1.

In the encoder 3 each discrete binary message signal duration τ _and converted packet coded FM signal in the FM signal packet messages from N = 4 digital signals with the same amplitude, equal to -1 or 1 (phase 0 or π). The thus formed packet of the FM message signal in the encoder 3 can be transmitted using phase modulation of 2-FM in a narrow bandwidth of the radio communication system.

In FIG. 6 shows the formation of the package of the FM message signal with amplitudes equal to -1 or 1.

From the output of encoder 3, a packet of FM message signals is fed to a phase shaper 6, after which it is transmitted by a phase modulator 7 of type 2-FM in a narrow passband of the radio communication system to a power amplifier 8 and is transmitted on a single carrier frequency to the communication channel using a transmitting antenna 9.

In the general case, narrow-band DKMV radio communication systems operate in a complex electronic environment due to the influence of both intra-system and external interference (multipath propagation, concentrated and pulsed interference, fast and slow fading, and others).

In view of the consideration of the potential characteristics of the proposed complex of means of protection, the influence of the communication channel on the operation of the receiving channel of the radio communication system is carried out under the following conditions [5, 7, 14, 17]:

- the attenuation of fading of the radio signals is assumed to be slow, since the duration of the packet of the FM message signal with a guard interval of τ _p ~ 18 ms is much less than the correlation time τ _k = 1 s at the level of 0.5 of the fading of the signal fading;

- random delays τ _s (t) between multipath signals are assumed to be from 2 to 4 ms (can reach more than 7 ms);

- the random nature of the above parameters has mainly a Rayleigh distribution, but there is a distribution according to the Rice law;

- that the amplitude of the FM radio signal of the message of the second beam a _{2 is} less than the amplitude of the FM radio signal of the message of the first beam a ₁ , i.e. a ₂ = 0.7 a ₁ , and the delay of the radio signal of the message of the second beam relative to the FM radio signal of the message of the first beam is assumed to be t _s = τ _p = 3 ms;

- Noise and impulse noise are considered as interference.

As an example, when modeling in a MathCAD environment, we consider the receiving side of a radio communication system with a bandwidth of Δ f = 300 Hz and an FM packet of a message radio signal including N = 4 discrete radio signals of duration τ _and = 3 ms with the same amplitudes equal to -1 or 1, and the guard interval τ _zi = 2 τ _and = 6 ms, which corresponds to a maximum delay τ _z = 6 ms between multipath signals.

After the receiving antenna 10, the microwave amplifier 11 and the phase demodulator 12, the message FM video packet is fed to the input of the communication computer module, which is additionally inserted on the receiving side of the radio communication system for converting and processing the message FM video signal packet.

At the output of the phase demodulator 12, the video signals of the first y _1c (t) and the second rays y _2c (t), taking into account the difference of their random phases ΔΨ and noise α (t), are determined by the formula:

where ΔΨ is a random phase difference in the range (0 ÷ π).

In FIG. Figure 7 shows, as an example, the amplitudes a _{1 of the} video signal with a duration τ _and = 3 ms of the first beam and noise α (t) at the output of the phase demodulator 12 with a passband of the radio communication system equal to Δf = 300 Hz.

In FIG. Figure 8 shows, as an example, at the output of the phase demodulator 12, the amplitudes of the sum y _c (t) and the difference y _p (t) of the FM signal signals of the first y _1c (t) and second rays y _2c (t) taking into account random mutual delays t _s = 3 ms and phase differences, respectively, ΔΨ = 0 and ΔΨ = 3π \ 4.

In FIG. 9 as an example, the output of the phase demodulator 12 is a mixture of noise α (t) and the amplitude of the sum y _c (t) and the difference y _p (t) of the FM signal signals of the first y _1c (t) and second rays y _2c (t) taking into account random mutual delay τ _s = 3 ms, signal-to-noise ratio q = 1 and phase differences, respectively Δ = 0 and ΔΨ = 3π \ 4.

At the input of the computational communication module, an analog-to-digital signal converter 13 is included, at the output of which a signal scale converter 14 is connected, which compresses the FM video signal packet in time to reduce its conversion and processing time in the computational communication module.

From the output of the signal scale converter 14, the FM video message packet is sent to the pulse noise compensation device 15, the use of which is explained as follows. Impulse noise is concentrated in time and is a random sequence of pulses having random amplitudes that vary from minimum to maximum over a time comparable to the time of a single interval, and following each other at random time intervals. In this case, impulse noise is superimposed on the useful signal in the phase demodulator, which leads to errors in the selection of phase information.

However, the compensation (cutting or reducing the level) of the impulse noise, which coincides with the discrete message signal, also causes an error in the phase information, therefore, at the output of the impulse noise compensation device 15, an interpolation device 16 is introduced, which, for example, according to two (or several) neighboring samples a packet of discrete message signals at the output of the pulse compensation device 15 restores phase information [18, 19].

In FIG. 10 eliminates a single error in the phase information arising from the action of pulsed interference.

From the output of the interpolation device 16, the packet of the FM video signal of the message arrives through the amplitude normalizing device 17 to the first input M = 4 of the channel decoder 18 with correlation processing, to the other inputs of which M = 4 source FM signals from the former of the source FM signals 19 arrive.

In FIG. 11 shows as an example the results of the correlation processing in the M = 4 channel decoder 18 of the noise mixture α (t) and the amplitude of the sum y _c (t) and the difference y _p (t) of the FM signal signals of the first y _1c (t) and second rays y _2c (t) taking into account random mutual delays τ _s = 3 ms, signal-to-noise ratio q = 1 and phase differences, respectively, ΔΨ = 0 and ΔΨ = 3π \ 4.

Due to the correlation processing in the M = 4 channel decoder 18, the spectral density of noise and noise when multiplied by copies of the original FM signals is expanded. As a result of this, in the narrow band of each channel of the correlator, the interference and noise powers are attenuated in accordance with the value of the base B = 4, i.e. there is an increase in the signal-to-noise ratio q by 6 dB [1, 3, 5].

From the output M = 4 of the channel decoder 18 with correlation processing, discrete message signals in the form of autocorrelation functions and noise are input to the adder of discrete signals 20. Moreover, due to the fact that the side lobes of the ACF do not exceed the level of 0.25 from the main lobe and are located in out of phase (see Fig. 3), when they are summed at the output of the M = 4 channel correlator, the side lobes of the ACF are eliminated (see Fig. 4).

In FIG. 12 are given as an example of the sum of the autocorrelation functions of the noise mixture α (t) and the amplitude of the sum y _c (t) and the difference y _p (t) of the FM signal signals of the first y _1c (t) and second rays y _2c (t) taking into account random mutual delays τ _s = 3 ms, signal-to-noise ratio q = 1 and phase differences, respectively, ΔΨ = 0 and ΔΨ = 3π \ 4 at the output of the adder of discrete signals 20.

In FIG. Figure 13 shows, as an example, the autocorrelation noise functions α (t) at the output from each of the M = 4 channels of the correlation processing decoder 18, from which it is seen that the autocorrelation noise functions α (t) are in antiphase, as are the side lobes of the ACF discrete message signals which is confirmed by the sum of the autocorrelation noise function α (t) at the output of the adder of discrete signals 20 shown in FIG. 14. As a result, at the output of the adder of the discrete signals 20, an increase in the signal-to-noise ratio q can be provided no less than N = 4 times, i.e. 6 dB.

Thus, due to the use of the OCDM technology bandwidth in narrow-bandwidth DKMV radio communication systems, the total signal-to-noise q gain in the communication computer module can potentially be at least 12 dB, which confirms the results of comparing the noise immunity of the OCDM technology compared to the use of OFDM technology in broadband radio communication systems given in [11]. This corresponds to a decrease in the probability of a bit error from P _b = 10 ^-2 to P _b = 10 ^-4 in a Gaussian communication channel while maintaining the previous probability of reliable data transmission [14].

From the output of the adder of discrete signals 20, discrete message signals are fed to the first input of the decisive threshold device 21, the second input of which receives the threshold voltage from the threshold shaper 22. The algorithm of the threshold decider 20 has the form:

where U _p (t) is the threshold level;

U _c (t) is the amplitude of the discrete message signal.

From the output of the decisive threshold device 21, the discrete message signals are fed to the input of the converter of discrete message signals 23, in which the discrete message signals are converted to a form convenient for the consumer.

Thus, the use of the proposed method for the protection of narrow-band radio communication systems in the complex electronic environment of the RDS software and hardware platform and the signal-code structure using OCDM technology at one carrier frequency allows you to:

- reduce the effect of multipath radio signals;

- to increase the noise immunity of the radio communication system while complicating the jamming environment by increasing the signal-to-noise ratio.

Literature:

1. Fink L.M. Theory of discrete message transmission / Fink L.M. - M .: Soviet radio. 1963.376 s. (prototype).

2. Sklyar, Bernard. Digital communication. Theoretical foundations and practical application. Ed. 2nd, rev .: Per. from English - M.: Publishing House "William", 2003. 1104 p.

3. Proxy John. Digital communication. Per. from English / Ed. D.D. Klovsky. - M .: Radio and communications, 2000. 800 p.

4. C. Feer. Wireless connection. Modulation and spreading methods. Per. from English / Ed. IN AND. Zhuravleva - M.: Radio and Communications, 2000.520 s.

5. V.A. Grigoriev, O.I., Lagutenko, Yu.A. Raspayev. Networks and radio access systems. - M .: Eco-Trends, 2005.384 s.

6. Varakin L.E. Communication systems with noise-like signals. - M.: Radio and Communications, 1985.384 s.

7. Keystovich A.V., V.R. Milov. Types of radio access in mobile communication systems: textbook. allowance / A.V. Keystovich, V.R. Milov. Nizhny Novgorod state tech. un-t them. R.E. Alekseeva. - Nizhny Novgorod, 2014.305 s.

8. Okunev Yu.B. Digital transmission of information by phase-modulated signals. - M .: Radio and communication. 1991.296 s.

9. Interference immunity and efficiency of information transmission systems / A.G. Zyuko, A.I. Falco, I.P. Panfilov et al. - M.: Radio and Communications, 1985.272 p.

10. Banquet V.L. Signal-code constructions of telecommunication systems. - Odessa: Phoenix, 2009.180 s.

11. Nikolaev V., Garmonov A., Lebedev Yu. Broadband radio access systems of the 4th generation: selection of signal-code constructions, Concern "Constellation", Scientific and Technical Journal "First Mile". Issue 5-6, 2010, 56-59 pp.

12. A.M. Belitsky, C.A. Postnikov, L.V. Strunskaya-Zlenko. The results of field tests of the radio channel based on the OCDM signal-code constructions. Theory and technique of radio communication No. 1/2015, from 48-53, JSC Concern Constellation.

13. RF patent No. 2663240. Method and complex of means for protecting narrow-band transmission channels in the conditions of multipath propagation of radio signals and a complex of means for its implementation.

14. Ermolaev V.T., Flaksman A.G. Theoretical Foundations of Signal Processing in Wireless Communication Systems: Monograph. - Nizhny Novgorod: Nizhny Novgorod State University, 2010.312 s.

15. Nikitin G.I. Application of Walsh functions in cellular communication systems with code division multiplexing: Textbook. allowance / SPbGUAP. St. Petersburg, 2003.86 s.

16. Ratynsky M.V. Fundamentals of Cellular Communication / Ed. D.B. Zimina - M.: Radio and Communications, 1998.248 s.

17. Gavrilenko, V.G. Radio wave propagation in modern mobile communication systems. Textbook / V.G. Gavrilenko, V.A. Yashinov. - N. Novgorod: NSU. 2003.148 s.

18. Radio engineering methods of information transfer: Textbook for universities / V.A. Borisov, V.V. Kalmykov, Y.M. Kovalchuk and others; Ed. V.V. Kalmykova. M .: Radio and communication. 1990.304 p.

19. Goncharov V.L. Theory of interpolation and approximation of functions. M., 1954. 327 p.

Claims (2)

1. A method for protecting narrow-band radio communication systems in a complex electronic environment, including on the transmitting side of the radio communication system the operations of generating messages, generating discrete signals, encoding discrete signals, generating phases, phase modulation, amplifying radio signals and emitting radio signals by a transmitting antenna, and including on the receiving side operations of receiving radio signals with a receiving antenna, amplification of microwave signals, phase demodulation, generating a threshold signal, solving thresholds the first separation of signals according to the likelihood criterion and the conversion of discrete message signals to a form convenient for the consumer, characterized in that on the transmitting side of the radio communication system, the operations of generating M = 4 source FM signals, adding M = 4 source FM signals to form from N = 4 discrete binary signals of the code FM signal in the form of a parallel assembly package containing information about M = 4 source FM signals, and on the receiving side, after the phase demodulation operation, operations of analog-to-digital signal conversion, signal scale conversion, impulse noise compensation, interpolation conversion to restore the received phase information signals, normalize the amplitude of the FM message signal, M = 4 channel correlation processing of the FM message signals containing information about M = 4 original FM signals, generating M = 4 source FM signals for M = 4 channel correlation processing, summing discrete signals with M = 4 channel correlation processing to ensure solutions to the threshold allocation of message signals according to the likelihood criterion. 2. A set of means for protecting narrow-band radio communication systems in a complex electronic environment, containing on the transmitting side of the radio communication system a series-connected message source, a digital signal conditioner, an encoder, a phase conditioner, a phase modulator, a power amplifier and a transmitting antenna, and on the receiving side it contains series-connected a receiving antenna, a microwave amplifier and a phase demodulator, as well as a decisive threshold device, the first input of which is connected to the output of the driver threshold, and the output of the decisive threshold device is connected to the input of the converter of discrete message signals, from the output of which information is supplied to consumers, characterized in that the transmitter of the initial FM signals of the transmitting side is additionally introduced on the transmitting side of the radio communication system, the outputs of which are connected to the corresponding inputs of the adder of the initial FM signals , the outputs of the adder of the initial FM signals are connected to the corresponding inputs of the encoder, and on the receiving side of the radio communication system shaper of the initial FM signals of the receiving side, a series-connected analog-to-digital signal converter, a signal scale converter for compressing in time the packet of the FM video signal of the message, an impulse noise compensation device, an interpolation device, an amplitude normalizing device and a decoder with correlation processing of the FM message signals whose outputs are connected to the corresponding inputs of the adder of discrete signals, the output of the adder of discrete signals connected to the second input I decide of the threshold device, the outputs of the source driver of the initial FM signals of the receiving side are connected to the corresponding inputs of the decoder with the correlation processing of the FM message signals, while the input of the analog-to-digital signal converter is connected to the output of the phase demodulator.

Images