SU1085010A1 - Phase-difference-shift keying detector - Google Patents

Description

Part 1

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01 The invention relates to communication technology and can be used when receiving discrete signals of relative phase telegraphy. A device for coherent detection of phase-shifted signals is known, the principle of which is based on narrowband filtering of the harmonics of the detection and synchronization frequencies of the master oscillator 1. However, the known device has a limited control region of the master oscillator, as the frequency range of the controlled oscillator decreases. own stability, since highly stable oscillators (quartz) have a limited control area, therefore, at low The stability of the carrier frequency of the transmitter may lead to interruptions in the reception of information, and with the expansion of the synchronization band, the noise immunity deteriorates. The closest in technical essence to the present invention is a relative phase telegraph detector comprising a trigger, a counter of a sequentially connected signal generator and a frequency selection block 2. However, noise immunity is not sufficient in the known device. B, invention - povnenie on resistance to impulse noise. The goal is achieved by the fact that a reference generator, a control trigger, an AND element and a coincidence unit are inputted to a relative phase telegraphy detector containing three characters, a counter, a serially connected signal generator and a clock selection unit, and the output of the clock selection unit is connected to the first control trigger inputs and a match block, the second inputs of which are connected to the output of the counter connected to the first input of the counter whose second input is connected to the output of the element I, the inputs of which connected to the output of the reference torus Generators and output control trigger the third input block matcher Cpd nen yield shaper and the output signal - to the input of the flip-flop. The drawing shows a structural electrical circuit of the proposed relative phase detector, howling telegraphy. The relative phase telegraphy detector contains a signal conditioner 1, a clock frequency selection unit 2, a 3-trigger trigger, a reference oscillator 4, an AND 5 element, a counter 6, a coincidence unit 7, a trigger 8. The relative phase telegraphy detector operates as follows. The phase-manipulated signal is fed to the driver 1 of the signal, where the input signal is formed into a digital signal in the form of square pulses fed to the block 2 for the selection of the clock frequency. The clock extracting unit 2 generates pulses from the carrier fronts, which then arrive at control trigger 3, which generates a command for allowing the frequency generator 4 to pass through AND 5 to b. The counting coefficient of the counter 6 is determined by the ratio of €; m the frequency of the reference oscillator and the carrier frequency of the channel, and the intersymbol distortion coefficient is Hfnf, where n is the counting coefficient of the counter 1. - the frequency of the carrier oscillation; TQ - the duration of the elementary information package. The filling counter 6 is reset by the output pulse, which also brings the control trigger 3 to the initial state and simultaneously arrives at the input of the coincidence unit 7. The inverted inputs of the coincidence unit 7 receive pulses from the clock extracting unit 2 and from the driver 1 of the signal. At the output of block 7 of coincidence, there appear pulses at the moments of time corresponding to the phase jump of the input so-nal, which arrive at the input of trigger 8. The trigger 8 generates a demodulated signal of relative phase telegraphy. In the case of the impact of impulse noise at the input of the detector, the relative phase telegraphy of the frequency of the pulses from the block 2 allocation clock frequency is violated. At the same time, the pulses of the counter b and the clock pulses of the clock selection block 2 do not coincide in time at the time of impact of the impulse noise; therefore, at the output of the coincidence unit 7 there are no pulses at this time and the trigger 8 remains in the initial state, i.e. does not react to the signal of interference coming to the third input of the owl block; adeny. The proposed relative phase telegraphy detector allows demodulation of the phase-shifted signal with enhanced noise immunity, when subjected to pulsed-interference at its input and non-11085010D

stability of the carrier frequency of the input with microminiaturization, it can

signal, as well as small intersym- be integrated microcircuit distortion. In addition, onma, which is an advantage over

does not require customization, (easy to match, compared with the known.

Claims (1)

: .571 RELATIVE PHASE TELEGRAPHY DETECTOR, comprising a trigger, a counter, a serially connected signal conditioner and a clock frequency isolation unit, which consists of the following: in order to increase the noise immunity from impulse noise, a reference oscillator and a control trigger are introduced into it, element 'And and a coincidence unit, the output of the clock allocation unit being connected to the first inputs of the control trigger and the coincidence unit, the second inputs of which are connected to the counter output connected to the first counter input, the second input coupled to an output AND gate whose inputs are connected to the output of the reference oscillator and the output of the control flip-flop, a third input matching block connected to the output signal _{from the} generator, and the output - © with an input trigger.