SU403011A1 - DEVICE FOR ACCEPTING THE PHASE OF THE BULLETS RIVANED - Google Patents

Description

one

The invention may find application in radio engineering and other areas related to the non-transmission of data to telephone communication channels.

Devices are known for receiving phase-shifted signals transmitted via telephone communication channels, consisting of a signal transducer block connected to a phase detector, one input of which is connected via a frequency divider and pulse driver to an adjustable sinusoidal generator, its control input is connected to the filter output low frequencies, and the last input - to the second phase detector connected to the pulse shaper and to the two outputs of the block transfer spectrum signal.

In order to improve noise immunity in the proposed device, the input of the first low-pass filter through the second low-pass filter additionally introduced in series and the switch connects the input of the zero-organ connected to the output of the first low-pass filter and connects the integrator output to the second input of the switch.

The drawing shows a block diagram of the proposed device.

The output of the signal transfer unit 1 of the signal is connected to the phase detector 2, as well as

phase detector 3 and frequency multiplier 4 on n (n is the modulation ratio). The second inputs of the phase detectors 2 and 3 are connected to the outputs of the driver 5 pulses,

the input of which is connected to the adjustable oscillator 6 through the frequency divider 7 on p. The output of the phase detector 3 is connected to the low-pass filters 8 and 9. The output of the filter 8 is directly connected to the adjustable oscillator 6 and through the null organ 10 and the filter I. In parallel to the filter 8 are connected in series a low-pass filter 9 and a switch 12 connected to a multiplier 4 via a band pass

filter 13, phase detector 14, integrator 15 and threshold device 16. The second input of phase detector 14 is connected to the output of the driver 5 pulses. The device works as follows.

The signal from the communication channel enters the signal transfer unit 1 of the signal, where it is transferred to a high carrier frequency and pulses are extracted from it, corresponding to zero signal transitions. The signal from the output of the spectrum transfer unit 1 enters the phase detector 3, and its second input receives signals from the pulse shaper 5, driven by the sinusoidal generator 6 being added, through frequency divider 7

on p.

The error signal from the output of the phase detector 3 is fed to the filters 8 and 9 of the lower frequencies. The signals from the filter outputs control the frequency and phase of the adjustable sinusoidal oscillator 6. Filter 8 has a narrow bandwidth, which gives high accuracy of coherent voltage separation, but at the same time capture time of adjustable oscillator 6 is high. To ensure high accuracy of selection of coherent voltage with small capture time parallel to the filter 8 through the switch 12 is connected an additional filter 9, having a wide bandwidth. In the capture mode, the switch 12 is closed, after the capture, it is opened, due to which an improvement in the receiver parameters is achieved.

The control signal of the switch 12 is generated by an additional circuit, in which an auxiliary coherent oscillation is extracted in an unshared manner. The circuit consists of a multiplier 4 on an n bandpass filter 13. Phase detector 14 compares the coherent and main coherent voltages. The signal from the output of the phase detector 14 is accumulated by the integrator 15 and is not connected to the threshold device 16. The signal from the output of the threshold device 16 closes the switch 12 when the main and auxiliary coherent voltages are synchronous, and the switch 12 doesn’t interrupt the oscillations interference.

In the frequency pickup frequency, the voltage at the input of the zero-organ 10 is not zero and has a definite sign indicating the direction of the mismatch between the frequency of the adjustable oscillator 6 and the signal at the output of the spectrum transfer unit 1.

Through the low-pass filter 8, the frequency of the oscillator 6 is quickly tuned, and the voltage applied to the generator is supplied to its input and its voltage is proportional to the frequency divergence.

Since the null organ 10 detects the presence and the sign of the mismatch, the filter 11 changes the level, its voltage at the output so that this mismatch is compensated. At the same time, the output of the filter 8 tends to a zero value, which is fixed by the null organ 10.

The low-pass filter 11 is computed from a large time constant (a good few

seconds), which allows you to get rid of

short-term uninterrupted, characteristic

for a telephone communication channel.

Subject invention

A device for receiving phase-shifted signals transmitted via telephone channels contains its spectrum non-transfer unit, the output of which is connected to one of the inputs of the first phase detector, to another input which is subsequently connected via a pulse shaper and a frequency divider output of a tunable siphusoidal NR generator to its the output of the first low-pass filter to the controlled input, to the input of which, through the second phase detector, the driver of nmnulses and the spectrum transfer unit are connected, connected via a frequency multiplier to the input of the nano filter, and its output is connected to the integrator via a phase detector, to another input of which is connected the second output of the pulse former, the third output of which is connected to the second input of the first phase detector, in order to improve noise immunity, to the input of the lowpass nerve filter through

The second low-pass filter, finally connected in succession, and the switch are connected to the input of a zero-organ connected to the output of the first low-pass filter, and to the second input of the switch

An integrator output is connected.

You m