Line radio with high secrecy of transmitted information

 

The invention relates to the field of discrete information transmission and can be used in radio channels to transmit information in space and terrestrial communication systems using pseudonoise signals. The technical result - increasing the secrecy of the transmitted information. For this purpose, the device comprises an information source, a phase modulator, balanced modulator, power amplifier, generator, SRP, generator carrier frequency synchronizer transmitter, modulo two, the switch, the shift register random number generator, transmitting and receiving antenna, a mixer, an intermediate frequency amplifier, a coherent filter, crucial unit, a receiver, a local oscillator, the clock of the receiver, n-1 agreed filters. In the device information 0 and 1 are possible, depending on the SRP of a given set different volume with a given repetition period. 4 Il.

The proposed device relates to the field of discrete information transmission and can be used in radio channels to transmit information in space and terrestrial communication systems using pseudonoise signals.

Known sisaly, the main disadvantage of which is low immunity due neoptimalizovat processing algorithm of the signal in relation to interference.

Also known radiotelephone communication system with photomanipulating noise-like signals (PSS) (see Varakin L. E. communication Systems with noise-like signals. - M.: RICE, 1985, S. 18, Fig.1-9). In the transmitter of a telephone message from an information source is fed to the input pulse-width modulator, the output of which the PWM signal is input to the phase modulator. To the second input of the phase modulator is served photomanipulating pseudonoise signal (FM PSS) generated by the generator FM. Photomanipulating the output signal of the phase modulator containing the information fed to the input of balanced modulator, which is balanced modulation with carrier frequency from the generator carrier frequency (GNC). Then from the amplifier the signal through the antenna radiates into space. The work of the pulse-width modulator and generator FM signal controlled by the synchronizer. The received signal in the mixer using lo is transferred to an intermediate frequency and after the amplifier is fed to the correlator, which is the optimal treatment prenatalcare contains a phone message in the form of a PWM signal, which is input to the demodulator, the output of which phone message is presented to the recipient of the information.

The main disadvantage of this device is low secrecy of transmitted information.

The closest to the technical nature of the claimed object is the device listed in the book Varakin L. E. communication Systems with noise-like signals. - M.: RICE, 1985, S. 16, Fig.1.7, adopted for the prototype.

Functional diagram of the device of the prototype is shown in Fig.1, where the following notation:

1 - source of information;

2 - phase modulator;

3 - balanced modulator;

4 - power amplifier;

5 is a pseudo - random sequence generator (gpsa);

6 - generator carrier frequency;

7 - the first synchronizer;

8 - transmit antenna;

9 - reception antenna;

10 - mixer;

11 - intermediate frequency amplifier;

12 - coherent filter;

13 is a decisive block;

14 - recipient information; and

15 - lo;

16 - the second synchronizer.

The device prototype has the following functional relationships. The transferor, the United information source 1, the phase modulator 2, the balanced modulator 3 and the amplifier 4, to the operator of the carrier frequency 6, and the second input of the phase modulator 2 is connected to the output of the generator SRP 5, the input of which is connected to the output of the first synchronizer 7. Reception party: reception antenna 9 is connected to the first signal input of the mixer 10, the second reference input connected to the output of the local oscillator 15, and the output of mixer 10 is sequentially connected to the intermediate frequency amplifier 11, a consistent filter 12, the deciding unit 13 and the receiver 14; in addition, the output of the matched filter 12 is connected to the input of the second synchronizer 16, one of the outputs connected to the input of the local oscillator 15, and the second output of the second synchronizer 16 is connected to a second input of the decision making unit 13.

Function prototype as follows.

From information source 1 a sequence of binary units 1 and zeros 0 with rate R=1/T is supplied to the first input of the phase modulator 2, where T is the duration of one information symbol. To the second input of the phase modulator 2 receives the signal pseudo-random sequence (SRP) from the pseudo-random sequence generator 5. Photomanipulating the signal produced by the phase modulator 2 has a duration T and is a sequence of the form of the Aza FM signal is approximately equal to the number of pulses, i.e., In=n

The generator SRP 5 controls the first synchronizer 7, which generates the necessary control signals and frequency. The sequence of PSS in the form of an FM signal carrying information symbols, enters the balanced modulator 3, which is balanced modulation of the oscillations of the carrier frequency of the FM signal. Oscillations with a carrier frequency generated by the oscillator carrier frequency 6.

The amplifier 4 amplifies photomanipulating signal to the required size and then through the transmitting antenna 8 radiates into space.

Adopted by the receiving antenna 9 signal fed to the mixer 10, where it is transferred with the help of the local oscillator 15 at the intermediate frequency is amplified in the intermediate frequency amplifier 11 and processed in a consistent filter 12. The output signal of the matched filter 12 is supplied to the second synchronizer 16 and a deciding unit 13.

The second synchronizer 16 searches the FM signal in frequency and time, accrue them to increase the reliability of the synchronization controls the operation mode deciding unit 13. To search for rebuilds the local oscillator 15. After finding and entering into synchronism at the output of the decision making unit 13 receive information posolstvo prototype has a low secrecy of transmitted information, because information 0 and 1 are encoded using only one SRP.

To eliminate this drawback in-line radio with high secrecy of the transmitted information containing on a transmitting side is connected in series source of information, a phase modulator, balanced modulator and the power amplifier, the output of which is connected to the transmitting antenna and the generator carrier frequency, the output of which is connected to a second input of the balanced modulator, and connected in series, the first synchronizer and the pseudo-random sequence generator, the output of which is connected with the second reference input of the phase modulator; at the receiving side receiving antenna connected to the first signal input of the mixer, the output of which through the intermediate frequency amplifier connected to the input of the first matched filter; in addition, the first output of the second synchronizer via the local oscillator connected to the second reference input of the mixer, and the second output of the second synchronizer connected to the second clock input of the decision making unit, the output of which is connected to the input of the receiver, the first signal input of the decision making unit is connected to the signal input of the second synchronizat which is connected to the output of the first synchronizer and to the input of the random number generator, the output of which is connected To inputs of the switch; however, the m outputs of the shift register connected to the m inputs of the switch, respectively, m outputs which is connected to the m inputs of the modulo two, respectively, the output of which is connected with the second clock input of the shift register; and the output of the shift register is the output of a pseudorandom sequence generator; at the receiving side entered n agreed filters and element I. the yield of the intermediate frequency amplifier connected to the n inputs of the agreed filters, amplifier, respectively, the outputs of which are connected to the m inputs of the element And accordingly, the output of which is connected to the signal input of the second synchronizer.

In Fig.2 shows a functional diagram of the proposed device, where we have introduced the following notation:

1 - source of information;

2 - phase modulator;

3 - balanced modulator;

4 - power amplifier;

5 is a pseudo - random sequence generator;

6 - generator carrier frequency;

7 - the first synchronizer;

8 - transmit antenna;

9 - reception antenna;

10 - mixer;

11 - intermediate frequency amplifier (if amplifier);

121- 12nfirst, second,..., nth Soglassye;

17 - item OR;

18 - modulo two;

19 - switch;

20 - the shift register;

21 - random number generator.

The proposed device has the following functional relationships. The transmitting side is connected in series source 1, the phase modulator 2, the balanced modulator 3 and the amplifier 4, the output of which is connected transmitting antenna 8; second input of the balanced modulator 3 is connected to the output of the generator carrier frequency 6; the output of the first synchronizer 7 is connected to the input of the pseudorandom sequence generator 5, the output of which is connected to a second input of the phase modulator 2; however, the pseudo-random sequence generator 5 includes a shift register 20, the first input of which is also the input of the pseudorandom sequence generator 5, a m outputs of the shift register 20 are connected to the m inputs of the switch 19, m outputs of which are connected to the m inputs of the modulo two 18 whose output is connected to the second clock input of the shift register 20, the output of which is also the output of a pseudorandom sequence generator 5; in addition, the first input of the shift register 20 through a pseudo-random number generator 21 com input of the mixer 10, the second reference input connected to the output of the local oscillator 15, and the output of the mixer 10 through the intermediate frequency amplifier 11 is connected to the m inputs of the agreed filters 121-12nthe outputs are respectively connected to the m inputs of the OR element 17, the output of which is connected to the signal inputs of the decision making unit 13 and the second synchronizer 16, the first output of which is connected to the input of the local oscillator 15, and the second output of the second synchronizer 16 is connected with the second clock input of the decision making unit 13, the output of which is connected to the input of the receiver 14.

The proposed device operates as follows.

From information source 1 a sequence of binary units 1 and 0 with rate R=1/T is supplied to the first input of the phase modulator 2, where T is the duration of one information symbol. To the second input of the phase modulator 2 receives the signal SRP from the pseudorandom sequence generator 5.

M-outputs of the individual bits of the shift register 20 are connected respectively to the m inputs of the switch 19, which controls the random number generator 21 that generates a random number in the range from 1 to n with repetition period L.

According to the random number generator 21, the switch 19 is the period of the SRP to the inputs of the modulo two 18, since the output of which the signal at the second clock input of the first digit of the shift register 20. Synchronizes the operation of the shift register 20 and the random number generator 21 of the first synchronizer 7.

Thus, for each bit of information will be used by the SRP, the number of which is determined by the random number generator 21.

The number of SRP obtained by switching the feedback, will be:

where(em) is the Euler function.

The random number generator 21 generates numbers in the range from 1 to n with period L. the Period can be chosen arbitrarily long and is selected according to the valid time of autopsy information TSS.

The random number generator 21 can be implemented in digital form on the basis of the recurrence relations. In this case, the period is calculated as follows:

ftis the clock signal; and

N=2m- the length of the SRP.

For example: at TSS=30 min ft=100 kHz, N=1023

The random number generator may also be performed based on the noise properties of electronic devices and then his period L=

Adopted by the receiving antenna 9 signal fed to the mixer 10, where it is transferred with the help of the local oscillator 15 at the intermediate frequency is amplified in the intermediate frequency amplifier 11 and is processed in one of n corresponding to the accepted signal consistent filter 121-12n, i.e., each of the n agreed filters tuned to one of the n structures of transmitted signals. The output signal from the corresponding matched filter 121-12nthrough the element OR 17 is supplied to the second synchronizer 16 and a deciding unit 13 searches the FM signal in frequency and time, accumulates the signal to increase the reliability of the synchronization controls the operation mode deciding unit 13. To search for a signal frequency of the second synchronizer 16 sweeps the frequency of the local oscillator 15. After finding and entering into synchronism at the output of the decision making unit 13 appears informaciok 5 is implemented by the scheme (see Fig.3) (Pestryakov Century B. Pseudonoise signals in communication systems. - M.: Owls. Radio, 1973, S. 147, Fig.4.2.3), where we have introduced the following notation:

1 is a generator of clock pulses;

21-2mfirst, second,..., m-th triggers;

31-3mfirst, second,..., m-th multipliers;

4 - modulo two.

Block 5 has the following functional relation.

The output of clock 1 is connected with the first signal inputs from the first to the m trigger 21-2mrespectively, and the outputs from the first to the m trigger 21-2mm multipliers 31-3mconnected to n inputs of the modulo two 4, the output of which is connected with the second signal input of the first trigger 21and, in addition, is the output device.

Work unit 5 as follows.

With the clock 1 pulses are received at the first signal input from the first to the m trigger 21-2mforming the shift registers. With outputs from the first to the m trigger 21-2mcorresponding to the singular values of the test polynomial signals through the m multipliers 31-3mproceed to the appropriate inputs of the modulo two 4, the output of which the signal is Ista.

In Fig.4 shows a block diagram of the block 19, which indicated the following: 191 - persistent storage device; 1921-192melements And.

N outputs a persistent storage device 191 is connected with the first inputs of n blocks 1921-192maccordingly, the outputs of which are outputs of the block 19, and the second inputs of the n blocks 1921-192mare the second input unit 19, respectively.

Unit 19 operates as follows.

K - bit signal from the block 21 is supplied To inputs (address bus) ROM 191, the output of which (data bus) m - bit signal (test polynomial M - sequence) is supplied to the first inputs of the blocks 1921-192maccordingly, the second input of which receives the m-bit signal from the block 20. The outputs of blocks 1921-192mare the outputs of the block 19.

If the discharge check polynomial (data bus block 191) unit, the signal of the shift register goes to the output unit 19 without modification, in the case of zero discharge, regardless of the value at the output of block 20 on the n outputs is set to logical zero.

The random frequency 21 can be implemented in the form of a pseudo-random number generator (SRP) is a shift register with amounts which acts comes a different number of summed signals. Therefore, it can be implemented in the form of a decoder with m inputs and one output. By law, the decryption will result in the following: when there is an even number of logical 1 at the input the output is logic 0; if odd number of logical 1 at the input the output is a logical 1.

Claims

Line radio with high secrecy of the transmitted information containing on a transmitting side is connected in series source of information, a phase modulator, balanced modulator and the power amplifier, the output of which is connected to the transmitting antenna and the generator carrier frequency, the output of which is connected to a second input of the balanced modulator, and connected in series, the first synchronizer and the pseudo-random sequence generator, the output of which is connected to the second reference input of the phase modulator; at the receiving side receiving antenna connected to the first signal input of the mixer, the output of which through the intermediate frequency amplifier connected to the input of the first matched filter; in addition, the first output of the second synchronizer via the local oscillator is connected to the second reference input of the mixer, and the second output Vtorov the om recipient information the first signal input of the decision making unit is connected to the signal input of the second synchronizer, characterized in that on the transmission side in a pseudo-random sequence generator entered the shift register, the first input connected to the output of the first synchronizer and to the input of the random number generator whose output is connected To inputs of the switch; however, the m outputs of the shift register is connected to the m inputs of the switch, respectively, the m outputs of which are connected to the m inputs of the modulo two, respectively, the output of which is connected to the second clock input of the shift register; moreover, the output of the shift register is the output of a pseudorandom sequence generator; at the receiving side entered n agreed filters and element OR with output of intermediate frequency amplifier connected to the n inputs of the agreed filters, amplifier, respectively, the outputs of which are connected to the m inputs of the element And accordingly, the output of which is connected to the signal input of the second synchronizer.

 

Same patents:

The invention relates to radio engineering

The invention relates to radio communication devices

The invention relates to radar systems and can be used in pulsed radar stations for correct reception of the echoes coming on the lateral petals (BL) of the antenna directional diagram (BOTTOM)

The invention relates to signal processing and, more specifically, to methods of signal processing for use in digital audio broadcasting (EEC)

The invention relates to communication systems, multiple access, code-division multiplexing (mdcr) and, more specifically, to a system power control direct communication channel from the base station to mobile stations

The invention relates to electrical engineering and can be used in receivers wideband signals

The invention relates to telecommunication systems

The invention relates to techniques for electrical connection and is intended for use in radio transmitting devices of high reliability

The invention relates to the field of radio and can be used to improve structural secrecy of signals in noise-immune systems

The invention relates to radio communications and can be implemented in space and terrestrial communication systems using sympodialis system and the spatial separation of signals

FIELD: radio communications; digital communication systems.

SUBSTANCE: proposed spectrum-division frequency modulator that incorporates provision for using frequency-modulated signals of high modulation index in communication systems where frequency resources are limited has two multipliers, two phase shifters, smoothing-voltage generator, two amplitude-phase modulators, carrier generator, adder, and frequency shift control unit.

EFFECT: enhanced noise immunity of communication systems.

3 cl, 15 dwg

FIELD: digital data transfers.

SUBSTANCE: proposed radio communication line that can use radio channels for data transfer, as well as return duplex radio communication control channels and burst-transmission radio networks for on-line radio command communications in unprotected regions is provided with newly introduced series-connected second single-pulse generator and second multidrop delay line, fourth, fifth, sixth, seventh, eighth, and ninth inverters, and series-connected second adder and second balance modulator introduced on transmitting end, as well as series-connected second correlator and fourth band filter, on receiving end. Proposed line incorporates provision for additional closure of data signal by means of other Barker code.

EFFECT: enhanced security of data transferred.

1 cl, 5 dwg

FIELD: radio engineering; construction of radio communication, radio navigation, and control systems using broadband signals.

SUBSTANCE: proposed device depends for its operation on comparison of read-out signal with two thresholds, probability of exceeding these thresholds being enhanced during search interval with the result that search is continued. This broadband signal search device has linear part 1, matched filter 2, clock generator 19, channel selection control unit 13, inverter 12, fourth adder 15, two detectors 8, 17, two threshold comparison units 9, 18, NOT gates 16, as well as AND gate 14. Matched filter has pre-filter 3, delay line 4, n attenuators, n phase shifters, and three adders 7, 10, 11.

EFFECT: enhanced noise immunity under structural noise impact.

1 cl, 3 dwg

FIELD: radio engineering for radio communications and radar systems.

SUBSTANCE: proposed automatically tunable band filter has series-connected limiting amplifier 1, tunable band filter 2 in the form of first series-tuned circuit with capacitor whose value varies depending on voltage applied to control input, first buffer amplifier 3, parametric correcting unit 4 in the form of second series-tuned circuit incorporating variable capacitor, second buffer amplifier 5, first differential unit 6, first amplitude detector 7, first integrating device 9, and subtraction unit 9. Inverting input of subtraction unit 9 is connected to reference-voltage generator 10 and output, to control input of variable capacitors 2 and 4. Automatically tunable band filter also has series-connected second amplitude detector 11, second integrating unit 12, and threshold unit 13. Synchronous operation of this filter during reception and processing of finite-length radio pulses is ensured by synchronizer 14 whose output is connected to units 10, 8, and 12. This automatically tunable band filter also has second differential unit whose input is connected to output of buffer amplifier 3 and output, to second control input of variable capacitor of band filter 2.

EFFECT: enhanced noise immunity due to maintaining device characteristics within wide frequency range.

1 cl, 1 dwg

FIELD: radio communications engineering; mobile ground- and satellite-based communication systems.

SUBSTANCE: proposed modulator that incorporates provision for operation in single-channel mode with selected frequency modulation index m = 0.5 or m = 1.5, or in dual-channel mode at minimal frequency shift and without open-phase fault has phase-shifting voltage analyzer 1, continuous periodic signal train and clock train shaping unit 2, control voltage shaping unit 3 for switch unit 3, switch unit 3, switch unit 4, two amplitude-phase modulators 5, 6, phase shifter 7, carrier oscillator 8, and adder 9.

EFFECT: enlarged functional capabilities.

1 cl, 15 dwg

FIELD: electronic engineering.

SUBSTANCE: device has data processing circuit, transmitter, commutation unit, endec, receiver, computation unit, and control unit.

EFFECT: high reliability in transmitting data via radio channel.

4 dwg

FIELD: electronic engineering.

SUBSTANCE: method involves building unipolar pulses on each current modulating continuous information signal reading of or on each pulse or some continuous pulse sequence of modulating continuous information code group. The number of pulses, their duration, amplitude and time relations are selected from permissible approximation error of given spectral value and formed sequence parameters are modulated.

EFFECT: reduced inetrsymbol interference; high data transmission speed.

16 cl, 8 dwg

FIELD: communication system transceivers.

SUBSTANCE: transceiver 80 has digital circuit 86 for converting modulating signals into intermediate-frequency ones. Signal source 114 transmits first periodic reference signal 112 at first frequency. Direct digital synthesizer 84 receives second periodic signal 102 at second frequency from first periodic reference signal. Converter circuit affording frequency increase in digital form functions to convert and raise frequency of modulating signals into intermediate-frequency digital signals using second periodic signal 102. Digital-to-analog converter 82 converts intermediate-frequency digital signals into intermediate-frequency analog signals using first periodic reference signal 112.

EFFECT: reduced power requirement at low noise characteristics.

45 cl, 3 dwg

FIELD: radio engineering; portable composite phase-keyed signal receivers.

SUBSTANCE: proposed receiver has multiplier 4, band filter 6, demodulator 8, weighting coefficient unit 5, adding unit 7, analyzing and control unit 10, synchronizing unit 3, n pseudorandom sequence generators 21 through 2n, decoder 1, and switch unit 9. Receiver also has narrow-band noise suppression unit made in the form of transversal filter. Novelty is that this unit is transferred to correlator reference signal channel, reference signal being stationary periodic signal acting in absence of noise and having unmodulated harmonic components that can be rejected by filters of simpler design than those used for rejecting frequency band of input signal and noise mixture. Group of synchronized pseudorandom sequence generators used instead of delay line does not need in-service tuning.

EFFECT: facilitated realization of narrow-band noise suppression unit; simplified design of rejection filters.

1 cl, 8 dwg

Up!