SU1195457A1 - Radio communication device - Google Patents

Abstract

The invention provides improved noise immunity. The information signal from the source of information 3 is fed to the transmitters 2 directly Or, via inverters 1, the signals from transmitters 2 located along the path through the channel 4 are fed to the receiver of a moving object. Through the broadband amplifier 5, the signal along with the noise enters the mixers 6 and 7, to the other inputs of which signals are fed respectively to frequency generators (MS) 9 and 8, whose frequencies lie above and below the frequency of the signal. Mixers 6 and 7 isolate the signal and interference with the difference frequencies of the HF 8 and 9. The conversion results are summed in adder 11 and fed to the multipliers 12 and t3. In multiplier 12, the signal of the adder 11 is multiplied with the sigma 10, the difference frequency voltage c the multiplier 12 through the delay line 14 is fed to another input of the multiplier 13. From the output of the multiplier 13, the resulting signal through the band-pass filter 15 is fed to a phase detector (PD) 18, to another input of the PD 18, a signal comes from the controlled phase shifter 16, C The drive from PD 18 goes to the information consumer through the low-pass filter 17 to the controlled phase shifter 16, to the other input of which the signal from the MS 1C, 1 slug arrives.

Description

one

The invention relates to a radio communication technique and can be used in diversity systems in systems using multi-frequency signals.

The purpose of the invention is to improve noise immunity.

The drawing shows the structural electrical circuit of the proposed device.

The wireless device contains inverters .1, transmitters 2 ,. information sources 3, communication channel 4, microband amplifier 5, mixers 6 and 7, frequency generators 8-10, adder 11, multipliers 1 and 13, delay line 14, band-pass filter 15, controllable phase shifter 16, low-pass filter 17 and phase detector 18.

The device works as follows.

The information signal from the source 3 is fed to the modulating inputs of the transmitters 2 or directly through the inverters. Transmitters 2 are located along the traos, on which it must be provided sv with a moving object. Transmitters with odd indices are tuned to frequency f. (And modulated by a direct signal, and with even ones - by f and modulated by an inverse signal. Signals that pass through channel 4 are fed to the receiver input of a moving object, where they are filtered from interference, which frequencies lie behind the band Frequencies occupied by the spectrum of the signal Interference with frequencies lying in the spectrum of the signal come together with the signal at the inputs of mixers 6 and 7. The frequencies of the generators 8 and 9 lie above and below the frequency of the signal (fp) and satisfy the ratio

 Cf ,, + ff.) K / if,

where k is the number of diversity channels;

f is the carrier frequency of the channel;

f ff. ff, are the frequencies of generators 8–10.

Mixers 6 and 7 select the components of the signal and interference with the difference frequencies of the generators 8 and 9. The results of these converters are summed by adder 11, Next

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An additive mixture of signal and interference is fed to the inputs of multipliers 12 and 13, the second input of multiplier 12 is supplied with a signal from generator 10. 5 Multiplier 12 draws the voltage difference from the mixing of the two input signals. The signal from the output of the multiplier 12 after a delay in line 14 is given

10 to the input of the multiplier 13, where the final phasing and summation of the signals is performed. The band-pass filter 15. has a bandwidth equal to the band occupied by the spectrum of a single signal, and separates the total voltage from the signals reduced to the frequency of the reference signal f. The magnitude of the delay of the signal in line 14 is equal to half the reciprocal of the frequency separation of signals with adjacent frequencies. Therefore, the carrier frequency modulated (FM) signals are subtracted, also fully subtracted

5 amplitude modulated (AM) oscillations (non-oscillating oscillations) and sideband components. The required frequency spacing is achieved by selecting the required carrier spacing, research institutes in channel 4 and selecting the frequencies of the generators 8 and 9 side components. FM signal bands are simulated in phase. Then the signal goes to the input signal of the phase detector 18 and to the information consumer.

Claims (1)

Invention Formula A radio communication device containing, on the transmitting side, channels, each of which consists of a transmitter, the first input of which is connected to the information source directly, and the second input through an inverter, and at the receiving side a broadband amplifier, the output of which is connected to the combined inputs of the first and second mixers, the second inputs of which are connected respectively to the outputs of the first and second frequency generators, as well as the series-connected phase detector, low-pass filter and controlled phase shifter, the output of which is connected to the first the input of the phase detector, and the second input is connected to the output of the third frequency generator, r.t.l and h and su3 11954574 Now that, with the purpose of the elevator, the output of which is connected to noise immunity, at the receive-second input of the multiplier, the second The side of the input of the first multiplier is connected to the connected adder, the first is renamed to the output of the third generator multiplier, delay line, secondj frequency, and bandpass filter output multiplier and band-pass filter, connected to the second input of the phase the outputs of the first and second detector, the output of which is mixers are connected to the inputs of the sum-output device.