SU1135005A1 - Pulse-repetition-frequency discriminator - Google Patents

Abstract

SELECTOR OF PULSES ON THE FREQUENCY OF INVESTIGATION, containing a delay element, the INPUT of which is connected to the input bus and the first input of the AND element, the output - to the second input of the AND element, the third input of which is connected to the output of the SHSh-NE element, and the output to the 1; In order to improve noise immunity by eliminating the suppression of selectable frequency pulses by interference pulses with following frequencies, the multiplicity of the selectable frequency was introduced, N additional elements were added (N is equal to the number of interference sequences with h crests, briefly selectable frequency), the inputs of each of which are connected to the taps from the parts of the delay element corresponding to the row t / p, 2 / p, 3 / p, ..., p-1 / p, where p for caldogr additional element It is determined by the frequency multiplicity of the interference and is a prime number of genus 2,; 3,5,6,11, ..., the outputs of all additional elements AND are connected to the inputs of the element ШШ-НЕ.

Description

WITH

ate

g 6

ate a dycod

1 / g f The invention relates to a radio, in particular, to a pulsed technique, and is intended for pulsing at a given frequency following against the background of random impulse noise and regular noise with frequencies that are multiples of the frequency selected. The closest to the proposed technical entity is a device containing an element of delay, the input of which is connected to the input bus and the first input of the element I, the output to the second input of the element AND whose output is connected to the output bus, and the element IPI-NE, output which is connected to the third input of the element And, and the inputs to the corresponding taps of the integer fractions of the delay element 1 J. A disadvantage of the known device is the suppression of the selected frequency pulses in cases where some or all of the sequences interference pulses will be delayed by a whole fraction of the follow-up period with respect to the pulses of the selected frequency. The purpose of the invention is to increase the noise immunity by eliminating the suppression of selected frequency pulses by interference pulses with frequency frequencies that are multiples of the frequency. The goal is achieved by the fact that the pulse selector has a following frequency, containing a delay element, whose input is connected to the input bus and the first input of the AND element, the output to the second input of the AND element, the third input of which is connected to the output of the OR-NOT element , and the output to the output PCB, N additional elements are introduced AND (N is equal to the number of interference sequences with frequencies that are multiples of the selectable frequency), the inputs of each of which are connected to the lead from the parts of the delay element corresponding to 1 / p, 2 / p, 3 / p, ..., p-1 / p, where p d Each additional element is determined and the multiplicity of the frequency interference, and is simple, the number of rows 2, 3, 5, 7, 11, .... and the outputs of all addi tional elements and connected to WMOs give OR-NO element. FIG. 1 shows a functional diagram of the proposed device for the case when a sequence of pulses of a selectable frequency is superimposed on two sequences of interference pulses with frequencies equal to two three frequencies of the selectable sequence; in fig. 2 - timing charts of the proposed device. The device contains a delay element 1, the element And 2, the element ILINE 3, the additional element And 4, input 5 and output 6 tires. The input of the delay element 1 is connected to the input bus 5 and the first input of the AND 2 element. The output of the delay element 1 is connected to the second input of the AND 2 element. The output of the OR-NOT 3 element is connected to the third input of the AND 2 element. The first input of the OR-NOT 3 element is connected From the 1/2 part of the delay element 1 (for the additional element And degenerates into a repeater and can be excluded). The second input element OR NOT 3 is connected to the output element AND 4, the inputs of which are connected to taps from 1/3 and 2/3 of the frequency of the element 1 delay. The output of the element And 2 is connected to the output shia 6. In FIG. 2 interference pulses are indicated by wavy lines, and the useful signal is a straight, thick line. FIG. 2a shows the input pulse sequence; in fig. 2 6.8 and g - sequences of impulses on the taps, respectively, of 1/3, 2/3 and 1/2 of the element 1 delay. The total delay time of element 1 is T (the period following useful pulses). FIG. 2D shows a sequence of useful pulses on the output bus 6. In the proposed device, pulses with a period of T / 3 are suppressed only when prohibition pulses that are delayed by time T / 3 and 2Т / 3 coincide. In the known device for the case shown in FIG . 2a, the useful pulses are perceived as interfering pulses with a frequency of 1 / 3T, and are suppressed. In the proposed device, the suppression of the useful pulses does not occur, and they arrive at the output bus 6 (Fig. 2e). In addition to the selector, the pulses must be normalized in amplitude and duration for normal operation with logic elements. To increase the efficiency of selection

Both the input and output can be pulse duration selectors, which filter additionally based on duration.

The application of the proposed pulse selector allows creating pulse impulse preprocessing systems with high noise immunity with a rather simple design.

FIG. 2

Claims (3)

PULSE SELECTOR BY FOLLOWING FOLLOWING, containing a delay element, the input of which is connected to the input bus and the first input of the AND element, the output is to the second input of the AND element, • the third input of which is connected to the output of the OR-HE element, and the output to the output bus, This is due to the fact that, in order to increase the mechanical protection by eliminating the suppression of pulses of the Selected frequency, interference pulses with repetition rates that are multiples of the selectable frequency, N additional AND elements are introduced (N is equal to the number of interference sequences with often s, kratnmi selectable frequency), each of which inputs are connected to taps of the delay element parts corresponding to row 1 / p 2 / p, 3 / p, ... "p-1 / p, where p for each I additional element And is determined by the frequency of the interference frequency and 'is a prime number from row 2, 3,5,6,11, ... ”and the outputs of all additional AND elements are connected to the inputs of the OR-NOT element.