SU921104A2 - Autocorrelation meter of parameters of pseudorandom phase-shift keying signals - Google Patents

Description

(54) AUTOMATIC CORRELATION METER OF PARAMETERS OF A PSEUDRONG PHASOMANIPULATED SIGNAL

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The invention relates to radio and can be used as a device for processing phase-shift keyed (FM) signals in discrete information transmission systems in combined communication systems and in radar.

According to the main author. St. No. 560343, there is a known autocorrelation meter for pseudo-random phase-manipulated signal paradieves, which contains series-connected multiplication unit, the input of which is connected to the output of the delay element, and a flat filter, as well as a low-pass filter, while the output of the tuning speed generator is connected to the first input of the delay element connected with the second input of the multiplication unit, the first input of the frequency meters, to the second inputs of which is connected, respectively, the output of the band pass filter No non-linear element and the first and second filters, low frequencies 1.

However, this meter has an inaccurate number of measured parameters.

The purpose of the invention is to increase the number of measured parameters.

The goal is achieved by the fact that a serially connected additional multiplication unit is inserted into a known autocorrelation parameter meter of a pseudo-random phase-manipulated signal,

5, a third low-pass filter, a gate, a pulse counter, a signal base meter and a registration unit, as well as a sequential package duration meter and an arithmetic unit, one input of the additional multiplication unit connected to the second input of the delay unit, and the other input to the output of the delay unit single frequency meter output

: through the parcel time meter is connected to the second input of the registration unit,

15, the third and fourth inputs of which are connected respectively to the output of another frequency meter and the output of the arithmetic unit, the other input of which is connected to the output of the signal base meter.

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FIG. 1 shows a structural electrical circuit of the proposed meter; in fig. 2 - vector diagrams for the job.

The device contains a multiplication unit 1, a delay element 2, a band-pass filter 3, a non-linear element 4, a low-pass filter 5, a tuning rate generator 6, a low-pass filter 7, frequency meters 8 and 9, a multiplication unit 10, a low-pass filter 11, a gate 12, a pulse counter 13, a signal base meter 14, a parcel length meter 15, an arithmetic unit 16, a registration unit 17.

The meter works as follows.

The received pseudo-random signal (Fig. 26) is fed to the inputs of multipliers 1, 10 and delay element 2, the delay value forming the first output of delay element 2 varies linearly with the tuning speed using a generator 6, which produces a periodic sawtooth control voltage . The amount of delay generated at the second output of delay element 2 is set constant. The second inputs of multipliers 1 and 10 receive the received FM signal, previously delayed in delay element 2. The multiplication result in multiplication unit 1 is high-frequency stuffing beats that pass through band-pass filter 3 and non-linear element 4. Filters 5 and 7 of the bottom The frequencies are tuned to the high-frequency filling, which is the carrier frequency of the FM signal, and the envelope, which is the clock frequency of the pseudo-random modulating function. The outputs of filters 5 and 7 are connected to frequency meters 8 and 9, to the second inputs of which the output periodically variable ramp voltage from generator 6 is fed. As a result, the output of frequency meter 8 removes information about the value of the clock frequency, and from the output of frequency meter 9 - about the value of the carrier frequency from the received signal.

The multiplication result in the additional multiplication unit 10 also results in high-frequency stuffing beats, the envelope of which is extracted by the low-pass filter 11.

This envelope is the product (Fig. 2) of two identical modulating functions (Fig. 2 a, d), shifted in time by the delay value.

The number of negative pulses in the signal is equal to the number of phase jumps of the received FM signal, and the duration of negative pulses is equal to the delay and does not depend on the duration of the elementary premises. Voltage (Fig. 2d) from the output of the low-pass filter 11 is fed to a unipolar valve 12, the output of which passes only negative pulses (Fig. 2, e). These pulses are counted by counter 13.

The number of phase jumps counted by the counter 13 enters the input of the meter base 1 of the signal 14, where the base of the signal is determined. Information about the value of the clock frequency from the output of the frequency meter 8 goes to the meter 15, where the clock pulses are formed (Fig. 2c), with which the duration of the elementary parcels is determined. The measured values of the signal base and the duration of the elementary parcels are fed to the arithmetic unit 16, where the duration of the received signal is determined.

Measured values enter the recording unit 17.

Thus, the proposed meter allows measuring not only the clock and carrier frequencies of the received signal, but also the duration of the elementary parcels, its base and the duration time.

Claims (1)

Invention Formula Autocorrelation meter of pseudo-random phase-manipulated signal according to aut. St. No. 560343, characterized in that, in order to increase the number of parameters to be measured, a series-connected additional multiplication unit is introduced, a third low-pass filter, a gate, a pulse counter, a meter the signal base and the registration unit, as well as a sequentially connected meter of the duration of the parcels and an arithmetic unit, with one input of the additional multiplication unit connected to the second input of the delay unit and the other input to the output the delay unit, the output of one frequency meter through the meter duration of the parcels connected to the second, the input of the registration unit, the third and fourth inputs of which are connected respectively to the output another frequency meter and the output of the arithmetic unit, the other input of which is connected to the output of the signal base meter. Sources of information taken into account during the examination 1. USSR author's certificate No. 560343, cl. H 04 B 3/46; 1976 (prototype).