SU1483665A1 - Receiver of discrete components of frequency signals with interpulse phase-shift keying - Google Patents

Abstract

The invention relates to communication technology. The purpose of the invention is to improve the reception accuracy by reducing the side maxima in the output signal. The device contains N channels consisting of bandpass filter 1, matched filter (SF) 2, delay block (BS) 3, and also adder 8. To achieve the goal, SF 4, phase detector 5, field selector 6 are entered into each channel of impulses and impulses 7. Each of the composite signal's ripo pulses is phase-manipulated by the corresponding 8-element binary code. In each pair of codes selected t.Obr. so that their autocorrelation functions have principal maxima that are the same in magnitude and sign, and the corresponding side maxima are equal in magnitude and opposite in sign. In autocorrelation functions that are phase-manipulated by these codes, this will lead to the antiphase character of the corresponding equal maximal side maxima and to the synphasicity of the principal maxima. 1 il.

Description

The invention relates to communication technology and can be used in receivers of discrete radio signals with intrapulse phase shift keying.

The purpose of the invention is to increase the accuracy of reception by reducing side maxima in the output signal.

The drawing shows a structural electrical diagram of the proposed device.

The device contains N channels, consisting of a band-pass filter 1, a first matched filter 2 2, a first matched delay block 3, a second matched filter 4, a phase detector 5, a pulse polarity selector 6 and a second delay unit 7, as well as an adder 8..

The device operates as follows.

The structure of the used discrete composite frequency signal with phase shift keying (DSCH-PSK) signal must satisfy the following conditions. At each of the N operating frequencies, two pulses of duration ΐ must be sequentially emitted, each of which is phase-manipulated by one of two codes that form a pair of codes that satisfies the requirements considered above. The time intervals T _s between the moments of emission of two pulses at the same frequency are selected FROM CONDITIONS T _with 7/2 4? _s

Consider the operation of the device at three different frequencies, each of the radio pulses of the composite signal being phase-locked by the corresponding 8-element binary code. At the first frequency, the first pulse is phase-shifted by the code - - - + + - - + -, the second pulse by the code --- +++ - +. At the second frequency, the first pulse is phase-shifted by a code - the second pulse - by a code - - + + - + +. At the third frequency, the first pulse is phase-locked by code. + - + + + + + 'second pulse - code

In each pair, the codes are chosen so that their autocorrelation functions have the main maxima of the same magnitude and sign, and the corresponding side maxima of equal magnitude and opposite in sign. The autocorrelation functions phase-shifted by these codes, it leads to the respective antiphase equal in magnitude to the side maxima and the main peaks in phase, the three-frequency ¹ RNG-PSK radio signal arrives at the device input.

At the outputs of the bandpass filters 1, signals are allocated to the inputs of the first and second matched filters 2 and 4. The matched filter in each channel is matched with the first phase-manipulated radio pulse, and the second matched filter 4 is matched with the second phase-manipulated radio pulse. The signals from the outputs of the matched filters 2 are fed to the inputs of the delay units. The delay intervals are selected in such a way as to ensure that the responses of the matched filters 2 and 4 to the signals matched with them coincide in time.

At the outputs of blocks 3, signals are fed to the phase detectors 5, the other inputs of which are fed from the outputs of the matched filters 4. At the outputs of the phase detectors 5, signals are generated that are bipolar sequences of video pulses that appear only when the signals are sent to both phase inputs detectors 5, At the same time, only the responses of the matched filters 2 and 4 to the signals matched with them can be received at both inputs of the phase detector 5. The responses of these filters to signals inconsistent with them are separated in time, and if there is such a response, there is no signal at only one I input of the phase detector at its output. At the output of the phase detectors 5, the sequence of video pulses has one pulse of positive polarity and the remaining pulses of negative polarity.

The signals from the outputs of the phase detectors 5 are fed to the inputs of the selectors 6 of the polarity of the pulses, which suppresses pulses of negative 'polarity. At the outputs of the selectors 6, signals are generated that arrive at the delay units 7. From the outputs of blocks 7, the signals are fed to the inputs of the adder 8, to the last input of which 5 1483665 6 signals are received directly from the output of the selector 6.

Claims (1)

Claim A device for receiving discrete composite frequency signals with intrapulse phase shift keying, consisting of an adder and N channels, each of which contains a band-pass filter, the input of which is the channel input and device input, and the output is connected to the input of the first matched filter, as well as the first delay unit, the output of the adder is the output of the device, which consists in that, in order to increase the accuracy of reception by reducing side maxima in the output signal, series-connected the second matched filter, phase detector and pulse polarity selector, with the output of the bandpass filter connected to the input of the second matched filter, the output of the first matched filter to the input of the first delay unit, the output of which is connected to the second input of the phase detector, and the output of the pulse polarity selector in all channels, except the last one, is connected to the input of the entered second delay unit, the output of which is connected to the corresponding input of the adder, while the output of the pulse polarity selector of the last channel connected to the last input of the adder.