SU471665A1 - Signal demodulator with pulse-phase modulation - Google Patents

Description

tel. The second input of the selective cascade 1 is connected to the control input of element 9, the signal input of which is connected to the generator of counting pulses 8, and forming stage 7, the output of which is connected to the multiple position matching element 13 and through element 15 to the register 12, the binary counter 10 and the peak detector 2, the output of the shaping stage 7 is connected to the control input of the number-carrying element 11.

The modulator operates as follows.

The mixture of the signal with pulse-phase modulation and noise is fed to the input 1 of the selection cascade 1, which is controlled by a gating pulse with a duration equal to the observation interval (channel scale) fed to the input 2 of the selection cascade 1. From the output of the selection cascade 1, the signal goes to the delay line 3 and a peak detector 2 with a large constant discharge time (in any case, a longer delay time). The voltage from the output of the peak detector 2, equal to the amplitude of observation of the corresponding surge (signal or noise) in the observation interval, serves as an automatically controlled level of limitation for a given delayed surge. The delay of the signal in the delay line 3 should somewhat exceed the duration of the measuring pulse. At the output of the output stage 4, the difference between the delayed signal and the voltage coming from the output of the peak detector 2 is formed.

After introducing an offset into the peak detector 2 or an appropriate selection of the transmission coefficient of the delay line 3 of the peak detector 2, the differential voltage at the output of the cascade 4 will be cut off all emission spikes (. Including noise) that occur on the channel scale. However, the maximum amplitude surge in the interval will always be the last. Therefore, the last burst at the output of cascade 4 must be taken as a measurement.

From the output of the cascade, 4 vertices of the selected outliers arrive at differentiating cascade 5, and from it through the amplifying-limiting cascade 6 to the shaping cascade 7. At the output of the forming cascade 7 short impulses will operate, the front of which coincides with the points of the maximum cutoff of signal and noise spikes .

The position of the point of maximum value of the pulses entering the amplifying-limiting cascade 6 is determined by the zero position of their derivatives.

Next, these pulses are fed to the control input of the multi-bit number 11 transfer element. Counting pulses from the generator of counting pulses 8 through element 9 are fed to a binary counter 10. Element 9 is opened with a gating pulse coming from the second stage 1 and having

Duration equal to the scale of the channel (observation interval). Counter 10 through the multi-bit number-transfer element 11 is connected to the register 12. Element 11 is used to overwrite the number from the binary counter 10: register 12. Element 11 is opened by pulses coming from the shaping cascade 7. Each time the number is rewritten from

the counter 10 to the register 12, will be proportional to the time interval between the beginning of the gating pulse (the beginning of the channel interval) and the selected pulse coming from the forming cascade 7. The number of transfers from counter 10 to register 12 will be equal to the number of emissions recorded on the channel interval.

The last transfer will correspond to the last pulse having the maximum amplitude.

Register 12 is polled through multi-element 13 at the end of a channel interval. The sampling pulse is obtained from the slice of the strobe pulse in the shaper 14. A demodulator output will have a number in the parallel binary code proportional to the time interval between the beginning of the channel interval and the temporal position of the last pulse corresponding to the temporal pulse with the maximum amplitude. The return of the demodulator to the initial state (reset of the peak detector 2, cleaning of the counter 10 and register 12) can be effected by an impulse from the output of the former 14 through the element 15.

The demodulator, by the position of the maximum value of the maximum pulse in the observation interval, allows using sufficiently simple technical means to ensure the accuracy and accuracy of fixation of the measuring pulses, which is almost close to the highest theoretically achievable with signals with an unknown phase.

Subject invention

A demodulator of signals with phase-pulse modulation, containing two-input selection and output stages, differentiating, amplifying-limiting and forming stages, a peak detector with two inputs, which are connected in series between themselves, and a delay line, the output of which is connected to the second input of the output stage, the input of the delay line is connected to the output of the selection cascade, characterized in that, in order to ensure the presentation of the results of the demodulation in digital form, the binary demodulator is included in the demodulator tchik with counting input and register with zero input multidigit number transfer element, multi element matcher connected between themselves

sequentially, shaper and element,

a delay signal, the outputs of which are connected to one of the inputs of the multiple position matching element and to the zero input of the binary counter and register and to the second input of the peak detector, respectively, a counting pulse generator and a two-input matching element whose output is connected to the counting input of the binary counter, and its

the inputs are connected to the generator of counting pulses and the connection point of the input of the imaging unit to the second input of the selection cascade, while the output of the shaping cascade is connected to one of the inputs of the multi-digit number transfer element, and the output of the imaging unit to the input of the element that delays the signal.