SU534022A1 - Device for compressing the dynamic range of signals - Google Patents

Description

The device works as follows.

The signals arriving at the input of the first channel are amplified at an intermediate frequency (IF) by the linear-logarithmic amplifier 4 and are fed to the first input of the adder I. At the input signal level i / in I, where I is the input voltage, starting from which the amplifier 4 characteristic becomes logarithmic, signals are linearly amplified in amplifier 4, and when the level of the input signals is f / Bx / ix, they are amplified according to a logarithmic law.

The signals arriving at the input of the second channel are amplified by the IF using a linear-logarithmic amplifier 5 and fed to the input of the amplifier-limiter 6 and the first input of the subtractive element 7, to the second input of which signals come from the output of the limiter amplifier 6. where LBXH is the input voltage from which the characteristic of amplifier 5 becomes logarithmic, the signals are linearly amplified by amplifier 5 and amplifier-limiter 6. At the level of the input signals of the second channel, the signals are amplified in amplifier 5 logarithmic law, and in the limiting amplifier 6 are limited. In the subtractive element 7, the output signals of the amplifier 5 and the amplifier-limiter 6 are subtracted. In this case, the amplitude characteristic of the second channel has three sections:

-at the level of the input signals f / Bx., f / vhn - linear section;

- at the level of the input signals / in, the inlet is a logarithmic section with a negative slope, where / in is the input voltage at which the output voltage of amplifier 5 becomes equal to the output voltage of amplifier limiter 6;

-at the level of input signals t / ax

ix is a logarithmic section with a positive steepness, where ii is the voltage at which the logarithmic amplitude characteristic ends.

In adder 1, the output signals of both channels are summed up; in this case, when the signals are in the first channel on the linear and logarithmic sections, and in the second channel on the linear section and the logarithmic section with a negative slope, the output signals of both channels are summed in phase.

and when the signals in the second channel are in a logarithmic section with a positive slope, the output signals of both channels are summed in antiphase (subtracted). If the signals in both channels are on logarithmic sections and f / Bx, then the total signal is, where Ko is the gain of one of the channels in the linear section.

If f / Bx, t t / Bx, the total signal will be larger or smaller than 2 / Cof / Bx by

/at

value a In

log slope where a

C / in.

rhymic characteristics of both channels, depending on which channel has the highest signal. The magnitude of the deviation of the sum signal from 2 / Cof Bx "is the signal

JOM errors. The total signal is compressed in time in the optimal filter 2, amplified by the IF and IFA and detected by the detector 3, after which the error signal is extracted and, moreover, the detected signals are used to determine the target distance and measure other parameters.

Claims (2)

Invention Formula A device for compressing the dynamic range of signals, mainly for receivers of monopulse direction finders, containing a series-connected adder, an optimal filter and detector, and two amplification channels over an intermediate frequency, the first of which consists of a linear-logarithmic amplifier whose output is connected to one of the inputs of the adder, and the second is of a serially connected linear-logarithmic amplifier and a limiting amplifier, characterized in that, in order to increase the degree of compression, the output to the line A log-logarithmic amplifier of the second channel is additionally connected to another input of the adder via a subtracting element, the other input of which is connected to the output of the amplifier-limiter. Sources of information taken into account in the examination: I. Leonov A.I. and others. “Monopulse radar, M.,“ Soviet Radio, 1970, p. 263 (equivalent). 2. US patent No. 3599208, 343-7A, 1971 (prototype). entrance