SU1054879A1 - Device for receiver automatic gain control of noise level - Google Patents

Abstract

AUTOMATIC REGULATION FOR ACCESSOR EFFICIENCY AT A CONVENTIONAL NOISE CONTAINER, containing a receiver of pulse signals, which in the form of a series-connected coaxed amplifier, an adjustable amplifier, to the input of which is connected through an amplifier, integrator, and detectors, and an adjustable amplifier, to the balanced input of which is connected through an amplifier integrator, and detectors of an adjustable amplifier; stability, between the output of the envelope detector. the first threshold element, the first binary-quantized signal generator, the subtraction unit and the low-pass filter are turned on and the integrator's input, and the serially connected second threshold element and the second binary-quantized generator) are connected between the output of the envelope detector and the other input of the subtraction unit signals. § 4A SB

Description

The invention relates to telecommunications and can be used to stabilize the amplification of receivers of pulsed signals at the level of a thum:

Devices for automatic control are known; receiver noise amplification (AGC), containing an adjustable amplifier and feedback circuit with a bending detector, which use frequency selectors G1 3 to separate noise emissions from useful pulse signals

However, in the known device frequency selectors are used, which do not ensure stable operation of the automatic gain control of the noise level in the receivers of pulse signals with overlapping spectra of the useful signal and noise.

The closest technical solution to the invention is a device for AGC receiver noise level, containing a receiver of pulse signals, implemented in the form of a series-connected matched filter, adjustable amplifier, to the control input of which is connected through an amplifier integrator, and an envelope detector

This device also has a low stability of the AGC in terms of the noise level in the receiver of the pulse signals due to the influence on its operation of the useful and interfering pulse signals.

The purpose of the Invention is to increase stability.

This goal is achieved by the fact that in a device for automatic gain control of a receiver, the noise level containing a receiver of pulse signals, fulfilled as a series-connected matched filter, adjustable amplifier, to the control input of which is connected through an amplifier integrator, and an envelope detector, between the output of the latter and the integrator's input includes serially connected first threshold element, the first driver of binary-quantized signals, a subtraction unit and a low-pass filter, and between the output of the detectors ora ogibaaschey and another input of the subtraction unit includes serially connected second threshold element and a second generator binary-quantized signals.

FIG. 1 shows a functional electrical circuit of the device; in fig. 2 is a timing diagram of a mixture of fluctuating noise (a), a pulse signal (b) and an ictattler (c) at the output of the envelope detector.

The device for noise receiver AGC contains a receiver of pulse signals 1, implemented in the form of serially connected matched filter 2, adjustable amplifier 3 and envelope detector 4, as well as the first and second threshold elements 5 and 6, the first and second drivers of binary quantized signals 7 and 8, subtraction unit 9, low pass filter 10, integrator 11 and amplifier 12.

The matched filter 2 can be switched on as before adjustable amplifier 3 (Fig.), And combined with it or turned on at the input of the envelope detector.

The device works as follows. From the output of the matched filter 2 through

5 adjustable amplifier 3 is an additive mixture of received pulsed useful and interfere-. of the receiver’s own fluctuation signal, enters the envelope detector 4. From the detector output 4, video0 signals, which are an additive mixture of the emission of schum and signal pulses (Fig. 2), arrive at threshold elements 5 and 6, which have different threshold levels and and 2. moreover, U., 1/2 When the video signal exceeds the specified threshold levels, the corresponding binary quantized signals S. are generated at the outputs of the formers 7 and 8. And 82 and the output of the subtraction unit 9 is a difference signal, i Low-pass filter 10 prednaz Achen for filtering transients, the formed due to the mismatch of intersection points Uj video signal threshold levels and 2. Next, the difference signal through the integrator II and amplifier 12 is fed to the control input of adjustable amplifier 3, ensuring that the gain of the receiving path of receiver 1 is adjusted according to the noise level at its input so that the level of noise at the output of the envelope detector 4 remains constant the action of destabilizing factors (ambient temperature, supply voltage).

Elimination of the influence of received pulsed signals on the operation of the AGC on the level of schum

5 is explained as follows. For the emission of a schum, the intensity of the signal flow S will always be greater than the intensity of the signal flow 82 If the threshold levels U. and and 2 are chosen such that

If the probability of increasing relative to the threshold level was P2 Р P, then this practically excludes the effect of the subtraction unit 9 and the operation of the AGC circuit in terms of the schum level, as in this case 8. , but

5, a slight difference in the intensity of the 8cI signals can be corrected by an appropriate choice of the gain factor of the amplifier 12.

On the other hand, the levels of impulse sigals and interference, as a rule, exceed the relative threshold level by 50 - 100%. Therefore, the vast majority of useful and interfering signal pulses exceed both the threshold levels: U and U, and the Si-S difference signal at the output of the subtraction unit when entering the input dt 10548794

The value of the useful pulse signal will be zero.

Thus, an increase in the AGC stability in terms of the noise level in the receiver of pulse signals with a matched filter is achieved by eliminating the influence of useful and interfering pulse signals.

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Claims (1)

DEVICE FOR AUTOMATIC REGULATION OF RECEIVER AMPLIFICATION BY NOISE LEVEL, containing a pulse signal receiver 'made in the form of a series-matched matched filter, an adjustable amplifier, to the ¹ control input of which an integrator is connected, and an envelope detector, characterized in that, for the purpose of increase stability between the output of the envelope detector. the first threshold element, the first generator of binary-quantized signals, the subtraction unit and the low-pass filter are connected in series with the integrator input, and the second threshold element and the second binary-quantized * signal generator are connected in series between the output of the envelope detector and the other input of the subtraction unit . w »SU,„. 1054879 Figure 1