RU2498503C2 - Radio communication system - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: transmitting part of the radio communication system includes two drivers, a FHSS signal generating device, a FHSS pseudorandom sequence sensor, a clock signal sensor, a signal switch, a transmitting part control unit, and the receiving part includes two radio receiving devices, two FHSS signal demodulators, a signal combining unit, a FHSS pseudorandom sequence sensor, a synchronising device and a receiving part control unit.

EFFECT: high concealment and noise-immunity.

5 dwg

Description

The invention relates to radio engineering and may find application in radio communication systems using broadband signals.

Known radio communication systems with pseudo-random tuning of the operating frequency (MHF), described in the monograph R.K. Dixon. “Broadband Systems”, Moscow, Communications, 1979 p. 327-328. And also in the monograph by A.A. Melnikova et al. “Radio links with software tuning of operating frequencies”, VOLKAS, Leningrad, 1982, pp. 9-26. “Interference immunity of radio systems with complex signals”, M., “Radio and communications”, 1985, pp. 138-146.

Closest to the technical nature of the claimed device is a communication system with frequency hopping described in the monograph Borisov V.I. “Interference immunity of radio communication systems with the expansion of the signal spectrum by the method of pseudo-random tuning of the operating frequency”, Moscow, Radio and Communications, 2000, p. 24, Fig. 7a and 7b, adopted as a prototype.

The structural diagram of this device is presented in figure 1. It contains:

The transmitting part, where:

1 - the first generator of pseudo-random code words (GPCS);

2 - the first frequency synthesizer;

3 - modulator;

4 - the first multiplier (mixer);

5 - frequency generator.

The receiving part, where:

6 - broadband filter;

7 - second multiplier (mixer);

8 - band-pass filter;

9 - demodulator;

10 - the second generator of pseudo-random code words (GPCS);

11 is a second frequency synthesizer.

The transmitting part contains the following functional relationships (figa):

- series-connected modulator (3) with the input of the transmitting part of the device and the first multiplier (mixer 4), the output of which is the output of the transmitting part, the frequency generator (5). the output of which is connected to the second input of the modulator, the output of the first GPCS (1) is connected to the second input of the first frequency synthesizer, 1 output of the first frequency synthesizer is connected to the input of the first multiplier (mixer).

The receiving part contains the following functional connections (figb):

- series-connected broadband filter (6) with the input of the receiving part;

- the second multiplier (mixer) 7;

- band-pass filter 8;

- a demodulator 9, the output of which is the output of the receiving part;

- series-connected second pseudorandom codeword generator (GPCS) 10, the output of which is connected to the input of the second frequency synthesizer 11, and the output of the latter is connected to the second input of the second multiplier (mixer) 7.

The device operates as follows. Digital information (message 0 to be transmitted is fed to the information input of block 3, to the second input of which harmonic oscillation is output from the output of block 5, in block 3, the harmonic oscillation is modulated by information symbols. The voltage from the output of block 3 goes to the input of block 4, to the second input which from the output of block 2 receives a signal whose formation law is determined by code words coming from the output of the SSCC.

In block 4, the signal is converted in accordance with the code words of the GPCS. The signal from the output of block 4 goes to the output of the transmitting part of the device.

In the receiving part of the device, the signal after filtering in block 6 is fed to the first input of block 7, the second input of which receives a signal from the output of block 11. The signal at the output of block 11 is synchronous with the signal at the output of block 2 of the transmitting part of the device.

After filtering in block 8, the signal is fed to the input of block 9, where it is demodulated and fed to the output of the receiving part of the device.

The disadvantages of the prototype are the inevitable loss of time when transmitting a message (transmission delay) due to the time required for tuning the radio frequency, the inability to pseudorandomly change the form of the emitted signal, since the modulator and frequency generator have constant parameters. In addition, the prototype device is designed to work only in the mode of slow frequency hopping, which reduces the intelligence and noise immunity of the radio link.

The aim of the invention is to increase the intelligence and noise immunity of radio communications through the simultaneous use of fast and slow software tuning of the operating frequency.

This goal is achieved by the fact that the radio communication system, containing in the transmitting part a modulator with a frequency generator, a pseudo-random code generator (GPS code), a signal multiplier, in the receiving part of the GPS code, a frequency synthesizer, a signal multiplier and a signal demodulator, additionally, a device is added to the transmitting part the formation of signals of fast software adjustment of the operating frequency (PPRCH-B), one of the inputs of which is the information input of the radio communication system, and the output is connected to the information input I will give the first and second drivers, the outputs of which are connected to the information inputs of the switch, the output of which is the output of the transmitting part, PPRCH-B signals are generated in accordance with pseudo-random code sequences received at the second input of the PPRCH-B signal generation device from the output of the pseudo-random code sequence sensor (DSPP-B), the input of which is connected to the output of the sensor synchronization signals synchronized in a single time, the signals from the sensor outputs also to the input of the control unit and to the input of the pseudo-random sequence sensor (DPSP-M), the output of the DPSP-M is connected to the input of the control unit. The outputs of which are connected to the remote control inputs of the first and second pathogens, the output of the control unit is connected to the input of the switch, the output of which is the output of the transmitting part of the radio communication system, the first and second radio receivers (RPU-1, RPU-2) are introduced into the receiving part of the radio communication system the outputs of which are connected to the inputs of the first and second signal demodulators with fast software frequency adjustment (PPRCH-B), in turn, the outputs of the first and second demodulators PPRCH-B are connected to the inputs of As for signal addition, the output of the signal addition unit is the output of the radio communication system, while to ensure control of the signal addition unit, one of the outputs of the control unit is connected to the input of the addition unit, and the second output of the signal addition unit is connected to the input of the control unit, the outputs of the control unit are connected to the inputs demodulator 1 and demodulator 2 PPRCH-B. Single time signals are supplied to the input of the synchronization device, the outputs of the synchronization device are connected to the inputs of DPSP-M and DPSP-B, as well as to the input of the control unit.

Figure 2 presents the transmitting part of the inventive radio communication system.

The transmitting part contains:

1 - a device for generating pseudo-random signals of fast program tuning of the operating frequency PPRCH-B;

2 - sensor (generator 0 pseudo-random code words for generating PPRCH-B signals;

3 - the first pathogen with automatic frequency tuning;

4 - the second pathogen with automatic frequency tuning;

5 - sensor (generator) of pseudo-random code words for generating signals of slow frequency hopping (frequency hopping-M);

6 - sensor signals synchronized by a single time;

7 - signal switch;

8 - control unit.

The digital signals to be transmitted are fed to the first input of the signal conditioning device (PPRCH-B) 1, to the other input of which pseudo-random codewords are received from the pseudo-random codeword sensor for generating PPRCH-B signals.

From the output of device 1, the generated signals are fed to the broadband inputs of pathogens 3 and 4.

The other inputs of the pathogens receive code words from the outputs of the control unit 8, in accordance with which the tuning of the pathogens in frequency in the frequency range, the width of which significantly exceeds the bandwidth of the broadband input of the pathogens, is provided.

From the output of the pathogens, frequency hopping signals are fed to the inputs of the switch 7, controlled by the commands of the control unit 8.

The alternate connection of the outputs of the pathogens to the input of the transmitter using the switch ensures the elimination of the delay in the transmission of messages due to the time of tuning of the pathogens, since during the time of tuning the frequency of one pathogen, the transmission of messages is carried out by another pathogen.

The output of the switch is the output of the transmitting part of the device connected to the input of the radio transmitter.

Figure 3 presents the receiving part of the inventive system. It contains:

9 - the first radio receiving device;

10 - the second radio receiving device;

11 - sensor (generator) of pseudo-random code words for generating fast frequency hopping signals (frequency hopping-B);

12 - sensor (generator) of pseudo-random code words for generating signals slow SADF (PPRCH-M);

13 - the first demodulator signals PPRCH-B;

14 - the second demodulator signals PPRCH-B;

15 is a synchronization device that provides the formation of pseudo-random signals in transmission and reception synchronously for signals of a single time;

16 is a block signal addition, providing the formation of a common stream of signals from the outputs of demodulator 1 and demodulator 2;

17 is a control unit that provides control of the blocks included in the receiving part, in accordance with the algorithm of the device, in part, which takes into account the time delay of the signals on the communication path, the time difference between the synchronization devices of the receiving and transmitting parts, etc.

The receiving part of the device operates as follows.

The received signals are fed to the inputs of the radio receivers 9 and 10 from the antenna (antenna amplifier). Reconfiguration of the radio receivers in accordance with the PPRCH-M signal generation program is carried out according to the control unit commands received at the inputs of the remote control systems of the radio receivers RPU-1 and RPU-2. Using RPU-1 and RPU-2, the isolation of PPRCH-B signals can be carried out in the entire frequency range of receivers in accordance with the program for generating PPRCH-M. The use of two radio receivers eliminates the loss of bandwidth of the radio channel due to the time spent on tuning the frequency of the radio receivers.

The signals transmitted in the PPRCH-B mode in the frequency band, the average values of which are determined by the PPRCH-M program, are fed from the outputs of the inverter RPU-1 and RPU-2 to the inputs of demodulator-1 and demodulator-2 of PPRCH-B, respectively. These demodulators demodulate the PPRCH-B signals in accordance with the DPSP-B code words coming from the output of block 11 through the control unit 17 to the other inputs of the PPRCH-B 13, 14. After demodulating the PPRCh-B signals, these signals from the outputs of the demodulators 13 and 14 enter the inputs of the signal addition unit 16, which is controlled from the control unit, one of the outputs of which is connected to the signal addition unit 16.

From one of the outputs of the signal addition unit, information is alternately supplied from the outputs of demodulators 13 and 14 to the recipient of the information.

From the second output of the control unit of the transmitting part, information is input to the input of the control unit 17, with the help of which the synchronization of demodulators is provided (tracking the delay of signals from PPRCH-M and PPRCH-B).

Figure 4 presents a timing diagram of the sequential adjustment of radio receivers.

The input of the synchronization device 15 receives signals from the single-time system, in accordance with which the initial installation of pseudo-random codewords generating programs for the PPRCH-M and PPRCh-B demodulators in DPSP-M 12 and DPSP-B 11 is carried out. Tracking the delay of the signals is carried out in the control unit 17, which receives the code sequence DPSP-M and DPSP-B, formed in accordance with the signals of a single time from the synchronization device 15 and the signals. Coming from the addition unit 16 when receiving synchronizing pseudo-random signals PPRCH-M and PPRCH-B.

The transmission of synchronizing pseudorandom signals precedes the transmission of information, and the form and method of generating synchronizing pseudorandom signals does not differ in the form and method of generating information signals.

Improving intelligence and noise immunity is ensured by reducing the time of radiation of the signal at each frequency (PPRCH-B) and expanding the frequency band within which the transmission of signals (PPRCH-M).

The timing diagram of the process of signal transmission using the combined mode PPRCH-M and PPRCH-B is presented in figure 5

Figure 5 conditionally, the duration of the message transmission is selected equal to 8 Δt, where Δt is the duration of the transmission of a fragment of the message in the frequency hopping mode (frequency band of the frequency hopping frequency is equal to Δt) at an average frequency of the band f. The frequency f is the pseudo-random frequency, fε [fmax], where [fmin, fmax] is the frequency band of the tuning of pathogens and receivers.

The duration of emission of signal elements at a fixed frequency in the PPRCH-B mode excludes the possibility of direction finding and aiming interference for each signal element, therefore, only obstructive interference in the entire frequency band of PPRCH-B signals can be effective, which will require a significant increase in the interference power.

Given the relative short duration of the signal emission in the PPRCH-B frequency band (changing the PPRCH-B frequency bands may be close to the tuning time of the receivers and exciters in frequency) and the complexity of detecting and detecting elements of the PPRCH-B signal, the task of suppressing a radio link with a combined (fast and slow ) MHF becomes intractable.

Thus, in the proposed communication system, the solution of the problem of increasing the intelligence and noise immunity of the radio communication system is ensured by the simultaneous use of fast and slow frequency hopping, while pseudo-randomly change both the average frequency of the frequency band PPRCH-B (in accordance with the code PPRCH-M), and signals used in PPRCH-B mode.

Claims (1)

A radio communication system comprising a modulator with a frequency generator, a pseudo-random code generator (GPS code), a signal multiplier in the transmitting part, and a frequency synthesizer, a signal multiplier and a signal demodulator in the receiving part of the GPS code, characterized in that a signal generating device is included in the transmitting part fast software tuning of the operating frequency (PPRCH-B), one of the inputs of which is the information input of the radio communication system, the output being connected to the information inputs of the first and second excitations Firs, the outputs of which are connected to the information inputs of the switch, the output of which is the output of the transmitting part, the PPRCH-B signals are generated in accordance with pseudo-random code sequences received at the second input of the PPRCH-B signal generation device from the output of the pseudo-random code sequence sensor (DPSP-B ), the input of which is connected to the output of the sensor of synchronization signals synchronized in a single time, the signals from the outputs of the sensor also go to the input of the control unit and to the input of the pseudo-random sequence sensor (DPSP-M), the DPSP-M output is connected to the input of the control unit, the outputs of which are connected to the remote control inputs of the first and second pathogens, the output of the control unit is connected to the input of the switch, the output of which is the output of the transmitting part of the radio communication system , the first and second radio receivers (RPU-1, RPU-2) were introduced into the receiving part of the radio communication system, the inputs of which are connected to the receiving antenna and are the input of the receiving part, and the outputs of RPU-1 and RPU-2 under are connected to the inputs of the first and second signal demodulators with fast frequency tuning (PPRCH-B), in turn, the outputs of the first and second demodulators PPRCH-B are connected to the inputs of the signal addition unit, the output of the signal addition unit is the output of the radio communication system, while control unit of the addition of signals, one of the outputs of the control unit is connected to the input of the addition unit, and the second output of the unit of addition of signals is connected to the input of the control unit, the outputs of the control unit are connected to the inputs of the demo unit 1 and demodulator 2 ППРЧ-B and to the inputs of RPU-1 and RPU-2, the signals of the same time are fed to the input of the synchronization device, the outputs of the synchronization device are connected to the inputs of the DPSP-M and DPSP-B, as well as to the input of the control unit, and the outputs of DPSP-M and DPSP-B are connected to the inputs of the control unit.

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