SU1215189A1 - Device for reception of pseudorandom phase-shift keyed signals - Google Patents

Abstract

The invention can be used in radiolocation, radio telemetry and radio transmission of information. Noise immunity. The mixer 5 receives an input high-frequency phase-manipulated broadband noise-like signal and a doubled carrier frequency signal from the controlled oscillator 4. From mixer 5, the signal through the multiplier 10, which separates the carrier frequency signal, phase-controlled according to the transmitted information, and band-pass filter II is fed to the third phase detector (PD) 13. The signal of the reference generator 1 arrives at the first PD 2 and through the frequency divider 14 into two pas another input of the third PD 13, which separates the binary symbols s information. The signal of the mixer 5 using the second PD of f., Schmidt trigger 7, delay line 8, and modulo two block 9 modulates a pseudo-random sequence delayed for a period that is fed to the multiplier. The signal of the bandpass filter P through the quad 12, which removes the information modulation, is fed to another input of the PD 2. The disparity signal with the PD 2 is fed through the filter of the 3-low frequency to the control input of the controlled oscillator 4. 1 Il. г С в ю 01 00 со

Description

Inventiveness relates to radio engineering and can be used in radio location, radio telemetry, and radio transmission of information for autocorrelation radio reception of phase-assisted broadband noise-like signals (FM 1Š11C).

The purpose of the invention is to improve noise immunity.

The drawing shows the electrical structure of the proposed device.

The device for phase-shift pseudo-random signals contains a reference oscillator 1, a first phase detector 2, a low-frequency filter 3, a controlled oscillator 4, a mixer 5, a second phase detector- .tor 6, a Schmidt trigger 7, a delay line 8, a block 9 of adders across module two, multiplier. 10, a band-pass filter 11, a quad 12, a third phase detector 13, a frequency divider 14 by two.

I.

The device works as follows.

in a way.

The corresponding input of the mixer 5 receives the input FM 11SH1C, and another input of the mixer 5 receives a double carrier signal from the controlled oscillator 4. From the output of the mixer 5 the signal at an intermediate frequency, which is equal to the carrier frequency, is fed to the inputs of the multiplier 10 and the second phase detector 6, on the second input of which frequency divider 14 for two receives the signal of the carrier frequency. At the output of the second phase detector 6, a pseudo-random sequence (PRS), distorted by noises, is released, which is fed to the Schmidt trigger 7, which forms rectangular pulses from it. From the output of the Schmidt trigger 7, the SRP enters the input line 8 of the delay, from the outputs of which are delayed relative to each other by several cycles of the SRP, is fed to the inputs of block 9 modulo-two adders, in which, as a result of modulation, these two SRPs form the same SRP, iad genre relative to the received per cycle (period nCIIj, and is fed to the second input of the multiplier 10. As a result of multiplying the high-frequency signal coming from the mixer 5 and delayed by the cycle

The bandwidth input from block 9 at the output of the multiplier 10. The rapi mono signal of the carrier frequency, which is phase-shifted in accordance with the information transmitted, is extracted. This signal is filtered from the noise by a band-pass filter 11 and is fed to the inputs of the third phase detector 13 and quadr 12, in which information modulation is removed by doubling the frequency. The narrowband harmonic signal of the doubled carrier frequency is fed to the input of the first phase detector 2, to the second input of which the output of the reference oscillator 1 is connected. The error signal from the output of the first phase detector 2 is fed through the low frequency filter 3 to the control input of the controlled oscillator 4. Besides In addition, the signal of the reference oscillator 1 through the frequency divider 14 is fed to the second input of the third phase detector 13, at the output of which binary information symbols are extracted. The proposed device uses a method for obtaining delayed memory bandwidths, based on the memory bandwidth property, which consists in adding two two memory bandwidths with different delay, but the same structure, with the same memory bandwidth with some other specific delay relative to the original memory bandwidth.

The formation of the SRP with a delay of the duration of the sequence period in the proposed device is carried out by a delay line 8 and a block 9 modulo-two adders. The delay line 8 has, in the general case, n taps, each of which ensures a delay of the SRP for the duration of the elementary symbol t (n is the degree of the generative polynomial of the SRP). The corresponding taps of the delay line 8 {depending on n and coefficients at the members of the generator polynomial of the bandwidth bandwidth) are connected to block 9 modulo two adders.

It should be noted that, in general, the maximum number of consecutive modulo-two summation operations that is required to obtain a memory bandwidth with any delay relative to the original memory bandwidth is d. This number is the smallest integer equal to or greater.

Thus, in the multiplier: 10, the high-frequency signal from the output of the mixer 5 multiplies and is delayed by the memory bandwidth generated at the output of block 9. At the same time, the power of the harmonic signal at the output of the multiplier 10 is almost equal to the power of the high-frequency input to its input signal (without taking into account losses in the multiplier 10).

Claims (1)

Invention Formula A device dp for receiving phase-manipulated pseudo-random signals, containing a series-connected reference oscillator, a first phase detector, a low-frequency filter, an adjustable oscillator, a mixer, and a second phase detector, to the second input of which the output of a frequency divider is connected to two, the input of which is 15189 the go is connected to the output of the reference oscillator, as well as a delay line, a third phase detector and a series-connected multiplier, 5 bandpass filter and quadrant, which is the fact that, in order to improve noise immunity, a modulo two adder block and a Schmidt trigger are introduced, the output of which through a delay line is connected to the modulo adder block two inputs, the output of which is connected to the first input multiplier, the second input of which is connected to the first 15 input of the second phase detector, the output of which is connected to the input of the Schmidt trigger, while the output of the bandpass filter is connected to the first input of the third phase-detector, 20 to the second input of which the output of the frequency divider is connected by two, and the output of the quad is connected to the second input of the first phase detector.