SU1007203A1 - Communication system with frequency separation of signals - Google Patents

Abstract

A COMMUNICATION SYSTEM WITH FREQUENCY DECOMPOSITION OF SIGNALS, containing on the transmitting side a source of information connected to the modulator and n spaced transmitters connected to n transmitting antennas, and on the receiving side K channels, where K, 2, 3.. .p, consisting of a receiving antenna connected to the receiver, and n phasing units, as well as a multi-channel adder, the output of which is connected to the reference inputs of the phasing units of all channels through the demodulation unit, in order to improve the noise immunity of the Effects under the action of impulse p interferences,. on the transmitting side, the modulator output and transmitter inputs are entered on the transmitter side with delay lines, and on the receiving side pulse shaper, the first and second delays with tapes are entered, and in each channel, on the channel - in series, the adder and key, all keys of all channels are connected to the inputs of the multichannel adder, and the second inputs of the adder are connected to the outputs of the phasing unit, the input of which is connected to the corresponding tap of the first line, the input of which is connected to the output of the receiver and the input ormirovatel pulses whose output via a second tapped delay line coupled to the control inputs of n tsimi keys. YU

Description

The invention relates to a radio communication technique and can be used in communication systems with diversity reception of signals to increase the noise immunity of reception under the action of high-power pulsed radio interference. A known device is a frequency diversity communication system, which on the transmit side contains transmitters whose outputs are connected to transmitting antennas and a modulator whose input is the input of the system and the output is connected to the input of one of the transmitters directly and on the receiving side each channel contains a receiving antenna, the output of each of which is connected to its receiver, as well as phasing units, one input of which is connected to the output of its receiver, and a multi-input adder, the output of which is connected to input b demodulation of an eye, the first output of which is the output device is of a different outlet connected to the reference inputs of the phasing blocks 1, however, such a system does not provide adequate noise immunity with respect to the action of powerful impulse noise. The purpose of the invention is to improve the noise immunity of reception under the action of impulse radio interference. The goal is achieved by the fact that the communication system with frequency separation of signals containing a source on the transmitting side. information is connected. with a modulator, and n spaced transmitters connected to n transmit antennas, and on the receiving side K channels, where K,, 2, W ... P, consisting of a receiving antenna connected to the receiver,. and n phasing blocks, as well as a multichannel adder, the output of which is connected to the reference inputs of the phase blocks of all channels through the demodule, the delay line with the taps is entered between the modulator output and the transmitter inputs, and the driver is entered at the receiving side impulses, first and second delay lines with taps, and in each channel - serially connected sum Gore and key, the outputs of the keys of all channels are connected to the inputs of the multi-channel adder, and the second inputs of the adder are connected to you odes is connected to a respective tap of the first delay line phasing unit, input, input connected to the output of the receiver and the input of the pulse shaper, the output of which through a second lit. NIJ tapped delay coupled with the control key inputs. FIG. 1 and 2 are given the structural electrical circuit of the transmitting and receiving part of the device. The device contains on the transmitting part a modulator 1, the output of which is connected to a delay line with taps 2 connected to transmitters 3 whose outputs are connected to transmitting antennas 4, and on each receiving channel contains receiving antenna 5 and receiver 6 in each receiving channel, the output of which connected to the delay line 7 with taps, each of which is connected to the "inputs of the phasing blocks 8, and the outputs of the phasing blocks 8 connected to the same taps of the delay lines 7 in all reception channels are combined in adders 9, the output of each of which is connected to the key 10, the output of which is connected to one of the inputs of a multiple input adder 11 connected to the input of the demodulation unit J12, the output of which is connected to the reference inputs of all the phasing units of the SV driver of 13 pulses, delay line 14 with taps connected to the control inputs of the corresponding keys 10. The phasing unit 8 consists of mixers 15 and 16 and a comb filter 17. The device operates as follows. at once. M-channel information is converted in modulator 1 into a signal, which is the sum of M oscillation subcarriers modulated by an angular modulation message and having a frequency difference between adjacent subcarriers equal to dso. This signal, having passed through a delay line with L taps 2, having a delay step equal to, is converted into L delayed signals that arrive at L transmitters 3, which emit signals at L different frequencies using the same number of antennas 4, and the spacing of neighboring frequencies The transmitters are chosen equal to the value of M-DbO. In this case, a multi-frequency signal is emitted from the air, containing the components, the frequency separation between which rabendoo. On the receiving side, the signal received by K of spaced antennas 5 and amplified by the same number of receivers 6 and fed to the inputs of K delay lines, each of L taps with a delay increment equal to. The signal generated by the output of the demodulator unit 12 is used as a reference in the KL phasing units 8. Assuming a high overall accuracy of the message reproduction by the whole system, the signals from the outputs of the delay lines 7 are given at the outputs of the mixers 15, filtered by delay line 17, the tuning frequency of the rushes are selected and the conditions

caL cotiColm-iVco ,,

where co, is the frequency of the signal at the output of the demodulator 12.

The signals from the OUTPUT of the delay line 17 are fed to the mixers 16. As a result of the conversion in the K th reception channel, at the frequency 00, the output of the mixers 16 of the phasing unit 8 produces signals, which are the coherently folded signals of the (Ld) transmitter (( d is the number of the withdrawal of the delay line 7). The remaining signals produced at the output of the mixers 16 have a spectrum lying outside the mixer filter band and are suppressed. AT

. adders 9 is the sum of such signals coming from the mixers 16 of all K reception channels.

In the absence of impulse noise, 10 are open and all signals from the L channels are added in adder 11. At the same time, in this communication system, LK is carried out. At a multiple, the optimal diversity of signal reception. If a powerful impulse, whose duration tviMn is less, acts on the input of all channels of the reception, then under the influence of this interference

. pulse generator 13 which

generates a pulse of duration Zy, with t j nn c it. This impulse is fed to the input of an additional delay line with taps 14, in which the delay of signals acting on

neighboring bends, equal. An impulse appears on these taps simultaneously with the appearance of signals at the corresponding taps of the delay line 17. At the same time, the keys 10 are open only for time intervals about, excluding the corresponding channel (one of the L channels) of the summing process at the output. As a result, at each given time interval a multiple of the value of b turns off only one channel and therefore the action of impulse noise does not lead to the complete interruption of information for the time of the interference (as is the case in the known system), but only to a certain reduction. The average signal energy ka is a time interval equal to And that means a significant increase in stability and reliability. communication compared with similar indicators of the known device. The economic effect of the invention is mainly determined by the savings that would be required

0 to transfer valid stations, a known communication system from a region of strong interference to radar stations in order to preserve the necessary reliability of communication.

m

Removal

Claims (1)

COMMUNICATION SYSTEM WITH FREQUENCY DISTANCE OF SIGNALS, containing on the transmitting side a source of information connected to the modulator, and η transmitters in space, connected to η transmitting antennas, and on the receiving side of K channels, where K, n 1 1, 2, 3 .,. n, consisting of a receiving antenna connected to the receiver, and η phasing units, as well as a multi-channel adder, the output of which through the demodulation unit is connected to the reference inputs of the phasing units of all channels, which means that, in order to · Increase of noise immunity at under the influence of pulsed radio interference, a delay line with taps is introduced on the transmitting side between the modulator output and the transmitter inputs, and a pulse shaper, the first and second delays with taps are introduced on the receiving side, and in each -. Nala - serially connected adder and the key, the key outputs of all channels are connected to the inputs of a multichannel combiner, a second combiner inputs coupled to the outputs of which Doodinen _l phasing unit, input to the corresponding first tap Li- <d SRI delay, whose input is connected to the receiver output and the input of the pulse generator, the output of which through the second delay line with taps is connected to the control inputs of the keys. Figure 1 th about Sae>