SU832756A2 - Pseudorandom signal receiving device - Google Patents

Description

(54) COMBINE PUSH-SAVING SIGNALS

I

The invention relates to radio communications and can be used in navigation radio links and pseudo-random signal communication devices.

According to the main author. St. No. 457182 known a pseudo-random signal receiver comprising a Pseudo-random sequence generator, a delay tracking unit including two filter integrators, two multipliers, a subtractor control element, a clock interrupter, a series-connected stable generator, a correlation pulse period meter, a period converter correlation pulses to frequency detuning code and code-voltage converter, the code-voltage converter output being connected One of the inputs of the control element of the delay tracking unit, in addition, the output of one filter integrator of the delay tracking unit is connected to the input of the correlation pulse period meter and to the input of the additional analysis unit, the other input of which is connected to the output of the detuning converter, and the output of the analysis block connected to the input of the converter of the period of correlation pulses lj "

However, the known device has a rather long acquisition time due to the need to re-measure the period of correlation moments.

The purpose of the invention is to reduce the time taken to synchronize.

This goal is achieved by c. a pseudo-random signal device containing a pseudo-random sequence generator, a delay tracking unit that includes two filter integrators, two multipliers, a subtractive device, a control element, a clock interrupter connected in series, a stable generator, a correlation pulse period meter, a period correlator of pulse correlation in the code. the frequency detuning and the code-voltage converter, the output of the code-voltage generator is connected to one of the control element inputs of the delay tracking unit, in addition, the output of one filter integrator of the delay tracking unit is connected to the input of the correlation pulse period meter and with the input of the additional analysis unit, the other input of which is connected to the output of the detuning converter, and the output of the analysis unit is connected to the input of the converter of the period of correlation pulses, into the delay tracking unit in edeny serially connected trigger lowpass filter and a controllable inverter to the corresponding input of which is connected to the output-code converter voltage and controls the inverter output emogo Cpd nen to one input of the control element, wherein the filtrovintegratorov outputs connected to inputs of the trigger. Fig, 1 shows a functional diagram of the device; in fig. 2 - diagrams for the device to work. The pseudo-randomlibix signal receiver contains a pseudo-random sequence generator, a delay tracking unit 2, which includes two integrator filters 3 and 4, two multipliers 5 and 6, a subtractor 7, a control element 8, a clock pulse chopper 9, a stable generator 10, and Correction pulse period meter 1I, period converter 12 and correlation pulses into frequency detuning code, frequency detuning code KID memory unit 13, code-voltage converter 14, analysis unit 15 trigger 16, filter 7 lower The controlled inverter 18, as well as the generator of 19 clock pulses, the device operates as follows., The analysis unit 15 switches on the mode of detecting the phase (delay) of the pseudo-occasional signal (PSS) by cyclically sliding the local signal from the input to the input snatch 9 clock pulses supplied to the input of the generator 1 pseudo-random sequence, and turn off the phase-locked loop by giving a signal to the reading device 7, If the signal at the receiver input is present at the outputs of the filter-integers rators 3 and 4, form (correlation of the input signal correlation peaks with the reference ones applied to the inputs of multipliers 5 and 6 (Fig. 2, plots a, b, c and d). The frequency of occurrence of the peaks is determined by the difference in the following input frequency and reference signals. A correlation pulse period meter 11 using a stable generator 10 determines a correlation peak period, the value of which is converted into a value (code) of a clock detuning of a clock generator. 19 clock pulses (the correlation peak frequency and the detuning frequency of this generator are interconnected a value called the MSS base using the correlation pulse-period converter 12 to the frequency detuning code. The frequency detuning code, through memory 13, ensures the storage of the This measurement to the next and playing the role of a smoothing device) is fed to the code-voltage converter 14. The voltage, the polarity of which is determined additionally by the introduced frequency detuning signal determination circuit, the executive body of which is the controlled inverter 18, goes to the control element 8. When the subtracting device 7 is turned on, the control element 8 adjusts the frequency of the 19-clock pulse generator. The analyzing unit 15 turns off the detection mode and turns on the phase-auto-tuning circuit of the clock pulse generator 19, i.e., prohibits the operation of the clock pulse chopper 9 and connects the subtractive device 7 to the control element 8 when the frequency detuning of the generator I9 occurs within the bandwidth limits elements of the subtractor 7 and the control element 8. The determination of the sign of the initial frequency detuning is carried out in a powerful way. It is known that the reference signals supplied from the generator 1 of a pseudo-random sequence to multipliers 5 and 6 are shifted relative to each other by an amount equal to twice the duration of the elementary symbol dog or by an amount approximately. equal to the peak width of the mutual correlation (for small frequency detuning). Since the input frequency of the input signal (which can also be significantly changed due to the Doppler effect) is unknown in advance, the local dog’s following frequency can be both higher and lower than the input following frequency, hence correlation peaks generated at the filter output -integrators 3 and 4 (Fig. 2, plots a, b, c and d) have different mutual temporal arrangement. For example, at one frequency detuning sign, a peak of correlation at the output of filter integrator 3 (Fig. 2, plot a) previously appears at the output of filter integrator 4 (fig. 2 plot b) and vice versa (vig plots).

The trigger 16 connected to the outputs of the filter integrators 3 and 4 triggers when each of the peaks appears and, depending on their sequence, forms at its output a high (with crushing) potential (Fig. 2, plot e) or low with pulses (Fig. 2 , zpyura e), which after filtering is using a filter. low pass 17 (Fig. 2, plots g and h) is applied as a control to a control inverter 18. The latter either inverts or leaves the polarity of the voltage supplied from the output of the converter 14 code-voltage to the control input unchanged. element 8. In the steady state, i.e., when the phase-locked loop is operating, a potential close to zero is formed at the output of the converter 14, and the state of the trigger 16 does not affect the operation.

Thus, the proposed device can reduce the time of entry into synchronism.

Claims (1)

1. USSR author's certificate No. 457182, cl. H 04 L 7/00, 1972 (prototype).  - -:: .: S 1