RU2156541C1 - Radio transmission line using phase-keyed noise- like signals - Google Patents

Abstract

FIELD: digital information transmission, radio channels of satellite and earth communication systems. SUBSTANCE: device has two information sources, pulse-width modulator, phase modulator, balance modulator, power amplifier, two FM generators, carrier frequency generator, two synchronization units, transmitting and receiving antennas, six mixers, intermediate frequency amplifier, correlator, demodulator, two information receivers, local oscillator, six band-pass filters, five electronic gates, adder, encoder, commutator, loop circuit, time- frequency matrix, reference oscillator and decoder. EFFECT: doubling transmitted information output. 4 dwg

Description

 The invention relates to the field of transmission of discrete information and can be used in radio channels for transmitting information in space and terrestrial communication systems using noise-like signals - SHPS.

 Known radio communication systems with noise-like signals, for example, by AS N 651492, which serves to transmit discrete information. The main disadvantage of this system is the low noise immunity under the influence of interference with a concentrated spectrum, which is due to the non-optimal signal processing algorithm with respect to such interference.

 A broadband communication system with ShPS is also known (see L.E. Varakin "Communication systems with noise-like signals", M., "P and C", 1985, p. 16, Fig. 1, 7), intended for transmission discrete messages. Since a matched filter is included in this device, using this device only incoherent reception of orthogonal signals is practically possible, which leads to insufficient noise immunity of information, since higher noise immunity is ensured by coherent reception and use of antiphase signals. In addition, the practical implementation of matched filters with large signal bases is a difficult technical task.

 The closest in technical essence to the proposed facility is a line of radiotelephone communication with phase-shift keyed fire alarm, given in the book of L. E. Varakin "Communication systems with noise-like signals." M., "P and C", 1985, p. 18, Fig. 1, 9, adopted as a prototype.

 The functional diagram of the prototype device is shown in FIG. 1, where the notation is introduced.

1 - source of information;
2 - pulse width modulator;
3 - phase modulator;
4 - balanced modulator;
5 - power amplifier;
6 - FM generator;
7 - carrier frequency generator;
8 - synchronizer;
9 - transmitting antenna;
10 - receiving antenna;
11 - mixer;
12 - intermediate frequency amplifier (UPCH);
13 - correlator;
14 - demodulator;
15 - recipient of information;
16 - local oscillator;
17 - FM generator;
18 - synchronizer.

 The prototype device has the following functional relationships. Transmitting device: a source of information 1 connected in series, a pulse-width modulator 2, a phase modulator 3, a balanced modulator 4 and a power amplifier 5, the output of which is connected to the transmitting antenna 9, the second input of the pulse-width modulator 2 is connected to one of the outputs of the synchronizer 8, the second output of which through the FM 6 generator is connected to the second input of the phase modulator 3, and the output of the carrier frequency generator 7 is connected to the second input of the balanced modulator 4. Receiving device: receiving antenna 10 is connected to one m from the inputs of the mixer 11, the second input of which is connected to the output of the generator 16, the input of which is connected to the first output of the synchronizer 18, the output of the mixer 11 through the IFA 12 is connected to one of the inputs of the correlator 13, the output of which through the demodulator 14 is connected to the input of the information receiver 15, the second output of the synchronizer 18 is connected to the second generator FM 17, the output of which is connected to the second input of the correlator 13, the third input of which is connected to the third output of the synchronizer 18 and the second input of the demodulator 14, and the input of the synchronizer 18 is connected inen with the output of the correlator 13.

 The device prototype works as follows.

 A telephone message (Fig. 2a) from the information source 1 is fed to the input of a pulse-width modulator 2. From the PWM output, the signal (Fig. 2b) is fed to the input of the phase modulator 3, the second input of which is supplied with an FM NPS (Fig. 2c), formed FM generator 6. The phase-manipulated signal from the output of the phase modulator 3 (Fig. 3d), containing information, is fed to the input of the balanced modulator 4, in which the balanced oscillation modulation with a carrier frequency from the carrier frequency generator 7 is carried out. Then, a 5 FM FM amplified by power the signal through the antenna 9 is radiated into space. The operation of the articulated-pulse modulator 2 and the FM signal generator 6 is controlled by a synchronizer 8, which generates the necessary frequencies and control signals.

 At the receiver, the signal received by the receiving antenna 10 enters the mixer 11, where, using the local oscillator 16, it is transferred to the intermediate frequency and after the IFA 12 it is transmitted to the correlator 13, which consists of a multiplier and an integrator. At the second input of the correlator 13, a reference signal from the FM generator 17 is supplied in the form of an FM NPS (Fig. 2c), and optimal processing of the received signal is performed in this correlator 13. The output of the correlator 13, thus, the voltage contains telephone messages in the form of a PWM signal, which is then fed to the input of the demodulator 14 and from the output of which the received telephone message is transmitted to the recipient of information 15. The operation of the receiver as a whole and its individual units (local oscillator 16, FM generator 17, the correlator 13, the demodulator 14) controls the synchronizer 18, which first searches for FM SPS by time and frequency, and then maintains synchronism.

 The disadvantage of the prototype device is the lack of bandwidth information.

 To increase the bandwidth of information to a device containing on the transmitting side - a series-connected information source, a pulse-width modulator, a phase modulator and a balanced modulator, a synchronizer, one of the outputs of which is connected to the second input of the pulse-width modulator, and the second synchronizer output through a generator FM is connected to the second input of the phase modulator, the output of the carrier frequency generator is connected to the second input of the balanced modulator, and a power amplifier whose output is dinen with transmitting antenna; on the receiving side, a mixer, an amplifier, a correlator, a demodulator, and an information receiver, a synchronizer are connected in series, one of the outputs of which is connected to the second input of the mixer through a local oscillator, the second output of the synchronizer through the FM generator is connected to the second input of the correlator, the third input of which is connected to the third output of the synchronizer and the second input of the demodulator, the output of the correlator, in addition, is connected to the input of the synchronizer, five mixers are introduced on the transmitting side, the signal inputs of which are connected between by itself and with the output of the balanced modulator, and the heterodyne inputs of these mixers are connected respectively to the five outputs of the encoder, the inputs of which are connected to the output of the second information source, the outputs of the five mixers through the corresponding bandpass filters are connected to the signal inputs of the corresponding five keys, the controlled inputs of which are connected to the five outputs a switch, respectively, whose input is connected to the sixth output of the encoder, and the key outputs are connected to the corresponding inputs of the adder, the output of which is connected on the input of the power amplifier; on the receiving side, the input of the bandpass filter is connected to the output of the correlator, and the output, through the recirculator, is connected to the input of the time-frequency matrix, the five outputs of which are connected respectively to the five inputs of the decoder, the output of which is connected to the input of the second information receiver, the reference generator, the output of which is connected with one of the inputs of the recirculator, two synchronizing inputs of which are connected respectively with two outputs of the synchronizer.

 In FIG. 4 shows a functional diagram of the proposed device, where the notation is introduced.

 From the 1st to the 18th designations are the same as in the prototype device.

On the transmitting side:
19 ₁ - 19 ₅ - mixers;
20 ₁ - 20 ₅ - band-pass filters;
21 ₁ - 21 ₅ - electronic keys;
22 - adder;
23 - encoder;
24 - switch;
25 - the second source of information;
On the receiving side:
26 - band-pass filter;
27 - recirculator;
28 - time-frequency matrix;
29 - reference generator;
30 - decoder;
31 - the second recipient of information.

 The proposed device has the following functional relationships.

Transmitting device: a first information source 1, a pulse-width modulator 2, a phase manipulator 3, and a balanced modulator 4, the output of which is connected to the inputs of five mixers 19 ₁ - 19 ₅ , the second inputs of which are connected respectively to the five outputs of the encoder 23, the input of which is connected in series coupled to the output of the second information source 25, the outputs of the five mixers ₁₉ January - 19 ₅ via a respective bandpass filter 20 ₁ - 20 ₅ are connected to the signal inputs of the corresponding keys ₂₁ January - 21 ₅ controlled inputs of which are connected to yati output switch 24, respectively, and the output of the switch 24 is connected to a sixth output of the encoder outputs keys ₂₁ January - 21 ₅ are connected to corresponding inputs of the adder 22, the output of which via the power amplifier 5 is connected to a transmitting antenna 9. The second input of the balanced modulator 4 is connected to the output the carrier frequency generator 7, and the second input of the pulse-width modulator 2 is connected to the output of the synchronizer 8, the second input of which through the FM generator 6 is connected to the second input of the phase modulator 3.

 Receiving device: serially connected mixer 11, UPCH 12, correlator 13, demodulator 14 and the first recipient of information 15, the signal input of mixer 11 is connected to the receiving antenna 10, the output of the correlator 13, in addition, is connected to the input of the synchronizer 18 and through the bandpass filter 26 - with one of the inputs of the recirculator 27, the second input of which is connected to the output of the reference generator 29, two synchronizing inputs of the recirculator 27 are connected respectively with two outputs of the synchronizer 18, the third input of which is connected to the second the input of the mixer 11, the fourth input of the synchronizer 18 through the FM generator 17 is connected to the second input of the correlator 13, the third input of which is connected to the second input of the demodulator 14 and the fifth input of the synchronizer 18. The output of the recirculator 27 is connected to the input of the time-frequency matrix 28, the five outputs of which connected respectively to the five inputs of the decoder 30, the output of which is connected to the input of the second information recipient 31.

 The proposed device operates as follows.

A telephone message (Fig. 2a) from the first source of information 1 is fed to the input of a pivot-pulse modulator 2. From the output of the PWM 2, the signal (Fig. 2b) is fed to the input of the phase modulator 3, the second input of which is fed to an FMB (Fig. 2c) generated by the FM 6 generator. The phase-manipulated signal from the output of the phase modulator 3 (Fig. 3d) containing information is fed to the input of the balanced modulator 4, in which the balanced modulation of the oscillation with the carrier frequency from the carrier frequency generator 7 is performed. From the output of the balanced modulator 4, the signal by steps to the input of the mixer 19 ₁ - 19 ₅ .

 From the second source of information 25, the second information is supplied to the input of the encoder 23 in the form of a binary digital code 25. The encoder 23 encodes the information. For example, the encoded information may take one of the following combinations of 10000, 01000, 00100, 00010, 00001.

According to this encoded information, the frequency synthesizer included in the encoder generates, respectively, five frequencies f ₁ , f ₂ , f ₃ , f ₄ and f ₅ , which from the five outputs of the encoder 23 can be supplied to the second (heterodyne) inputs of the mixers 19 ₁ - 19 ₅ . Moreover, in the interval of the signal duration from 0 to T, only one of the five frequencies comes from the output of the synthesizer, depending on the transmitted information. The beginning and duration of periods of information signals transmitted from the first and second sources of information must coincide.

The signal from the outputs of the mixers 19 ₁ - 19 ₅ through the corresponding band-pass filters 20 ₁ - 20 ₅ is fed to the signal inputs of the corresponding keys 21 ₁ - 21 ₅ . The input of the switch 24 from the encoder 23 is encoded information, for example, 10000, 01000, 00100, 00010, 00001, depending on the transmitted information.

The five-output switch controls keys 21 ₁ - 21 ₅ accordingly. So, for example, if switching 10,000 is received on the switch, then the first key 21 ₁ will open, if - 01000, then the second key 21 ₂ will open, etc.

From the outputs of the keys 21 ₁ - 21 _{5, the} signal through the adder 22 is fed to a power amplifier 5, where it is amplified to the required value and radiated through the antenna 9 into space.

 In the receiver, the signal received by the antenna 10 enters the mixer 11, where, using the local oscillator 16, it is transferred to the intermediate frequency and, after amplification to the amplifier 12, where it is amplified to the required value, it is transmitted to the correlator 13, which consists of a multiplier and an integrator. At the second input of the correlator 13, a reference signal from the FM generator 17 is supplied in the form of an FM NPS (Fig. 2c) and optimal processing of the received signal is performed in this correlator. The output of the correlator 13, thus, the voltage contains a telephone message in the form of a PWM signal, which is then fed to the input of the demodulator 14 and from the output of which the received telephone message is transmitted to the first recipient of information 15.

The signal from the output of the correlator 13, in addition, is fed to a band-pass filter 26. The band of this filter should be equal to the frequency range f ₁ - f ₅ , based on the frequencies of the transmitter, plus the instability of the frequencies of the transmitter and receiver, that is
Δf = Δf + δf _{under Tx} + δf _CSTR
From the output of the bandpass filter 26, the signal is fed to the recirculator 27, where the signal is accumulated. The shear frequency for the recirculator is equal to the bandwidth of the broadband filter Δ f and equal to the frequency of the reference oscillator.

The delay time of the delay line of the recirculator should be equal to τ _lz = 1 / Δf.
The cycle of signal accumulation in the recirculator is equal to T, that is, equal to the period of the transmitter signal.

In the time period from 0 to T, only one of the frequencies f ₁ , f ₂ , f ₃ , f ₄ , f _{5 is} present. At the end of the period of the signal from the synchronization unit 18, a read pulse U _s (see Fig. 3a) is received and immediately after it is a blanking pulse U _g (see Fig. 3b). Moreover, the trailing edge of U _with coincides with the leading edge of U _g . The durations U _c and U _g are equal to each other and equal to the duration of the delay line τ _{ls of the} recirculator.

After the action of U _g , the recirculator 27 is zeroed. Next, the accumulation cycle is repeated. Thus, the recirculator is a block in which the accumulation of signals with frequencies f ₁ , f ₂ , f ₃ , f ₄ and f ₅ occurs. Depending on the transmitted frequency from the ensemble, through f ₁ - f _{5 the} position of the convolution of the signal in U _s will change. So, if the frequency f _{1 was} transmitted, then this will correspond to interval 1 (see Fig. 3d) - U _с1 - in the read pulse U _с (Fig. 3c), if f _{2 was} transmitted, then to the interval two U _с2 , etc. .

The time-frequency matrix 28 converts the time interval U _с1 - U _с5 into a code (Fig. 3d, d, ... e).

 And then the decoding unit 30 provides the second information to the second recipient of information 31.

 Thus, the proposed device due to minor complications allows you to double the amount of transmitted information.

Claims (1)

 A radio communication line with phase-shift keyed oscillator circuits containing on the transmitting side a first information source, a pulse-width modulator, a phase modulator and a balanced modulator, a synchronizer, one of the outputs of which is connected to the second input of the pulse-width modulator, and the second synchronizer output is connected via the FM generator to the second input of the phase modulator, the carrier frequency generator is connected to the second input of the balanced modulator and a power amplifier, the output of which is connected to traveling antenna; on the receiving side there is a series-connected mixer, an amplifier, a correlator, a demodulator, and a first information receiver, a receiving antenna is connected to the input of the mixer, a synchronizer, one of the outputs of which is connected through a local oscillator to the second input of the mixer, and the second output of the synchronizer through the FM generator is connected to the second input of the correlator the third input of which is connected to the third output of the synchronizer and the second input of the demodulator, the output of the correlator, in addition, is connected to the input of the synchronizer, characterized in that and on the transmitting side there are five mixers, the signal inputs of which are connected to each other and with the output of the balanced modulator, and the heterodyne inputs of these mixers are connected respectively to the five outputs of the encoder, the input of which is connected to the output of the second information source, the outputs of the five mixers are connected to the signal inputs through the corresponding bandpass filters the corresponding five keys, the controlled inputs of which are connected to the five outputs of the switch, respectively, whose input is connected to the sixth output of the encoder, and the outputs to yuchey connected to respective inputs of an adder whose output is connected to the input of the power amplifier; on the receiving side there is a band-pass filter, the input of which is connected to the output of the correlator, and the output through the recirculator is connected to the input of the time-frequency matrix, the five outputs of which are connected respectively to the five inputs of the decoder, the output of which is connected to the input of the second information receiver, the reference generator, the output of which connected to one of the inputs of the recirculator, two synchronizing inputs of which are connected respectively with two outputs of the synchronizer.

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