SU1169191A1 - Device for reception of signals with synchronous keying - Google Patents

Abstract

DEVICE FOR RECEIVING SIGNALS WITH SYNCHRONOUS MA NIPULYATSIEY comprising a frequency divider, a synchronous detector having a first input kotopoio combined with a first input of multiplier and is an input device, the second input of multiplier is coupled to one input of the generator support sihnalov, Drukh whose output is connected to the first input of the discriminator } the second input of which is connected to the output of the synchronous detector, and the output of the multiplier is connected to the first input of the phase-locked block of the automatic frequency control, characterized by the fact that and noise immunity and accuracy of evaluation of the random time delay of the present, a low-pass filter, a phase shifter and a random delay estimator are entered into it, the discriminator output being connected to the low-pass filter input and the second input of the phase-locked loop, the output of which is connected to the second input synchronous detector, the first input of the random delay evaluation unit, and through a frequency divider with the input of the phase shifter, the control input of which is connected, with the output of the lower hour filter That is, the output of the phase shifter is connected to the input of the reference signal generator and the second input of the random delay estimator to which the output is the ustoe output. roystva

Description

The invention relates to radio engineering and can be used in complex radio communication and radiolocation systems.

A device for receiving signals with synchronous manipulation is known, comprising a frequency divider, a synchronous detector, the first input of which is combined with the first input of the multiplier and is the input of the device, the second input of the multiplier is connected to one input of the reference signal generator, the other output of which is connected to the first input of the discriminator , the second input of which is connected to the output of the synchronous detector, and the output of the alternator is connected to the first input of the phase locked loop 1. However, the known device possesses insufficient noise immunity and accuracy of estimation of the random signal time delay.

The purpose of the invention is to improve the noise immunity and accuracy of estimation of a random signal time delay.

The objective is achieved in that a device for receiving signals with synchronous manipulation, containing a frequency divider, a synchronous detector whose first input is combined with the first input of the multiplier and is the device input, the second input of the multiplier is connected to one input of the reference signal generator, the other output of which connected to the first input of the discriminator, the second input of which is connected to the output of the synchronous detector, the output of the multiplier is connected to the first input of the phase locked loop, a filter is introduced Frequency, phase shifter and random delay estimator, the discriminator output is connected to the low-pass filter input and the second input of the phase locked loop whose output is connected to the second input of the synchronous detector, the first input of the random delay estimator and the phase shifter whose control input is connected to the output of the low-pass filter, the output of the phase shifter is connected to the input

the reference signal generator and the second input of the random delay estimator; the output of which is the output of the device.

FIG. 1 shows a structural electrical circuit of the proposed device; in fig. 2 is a block diagram of a random delay estimator; in fig. 3 shows timing diagrams explaining the operation of the random delay estimator.

The receiving device comprises a synchronous detector 1, a discriminator 2, a low-pass filter 3, a generator of 4 reference signals, multiplier 5 ,. a phase locked loop 6, a frequency divider 7, a phase shifter 8, a random delay estimate calculation unit 9. Block 6 consists of a phase detector 10, an adder 11, a low-pass filter 12, a controlled oscillator 13, and a phase shifter 14. Block 9 consists of a short pulse shaper 15, a gate shaper 16, and a coincidence block 17.

The device works as follows.

The inputs of the synchronous detector 1 and multiplier 5 receive a received signal, the phase and temporal position of the envelope of which depend on the change in the random time delay. As a result of multiplying the received signal with the video signal of the generator 4, at the output of the multiplier 5, a carrier frequency oscillation is produced. In block 6, the controlled oscillator 13 is synchronized in frequency and phase with the output signal of the multiplier 5. From the output of the discriminator 2, the voltage proportional to the time error between the demodulated signal and the pulses of the generator 4, goes directly to the adder 11 of block 6 and through the filter 3 lower frequencies to the control input of the phase shifter 8, thereby changing the reference clock oscillation period, which is formed by the frequency divider 7 from the high frequency oscillation of block 6.

Therefore, tracking the temporal position of the envelope of the received signal, taking into account the additional information about the change in the random time delay contained in phase 3 of the carrier frequency, improves the noise immunity of the device and the accuracy of estimation of the random time delay. The increase in noise immunity is achieved due to the fact that block 6 with high accuracy tracks the dynamics of the change in the time delay. This allows the lowpass filter 3 to be made narrowband, which is equivalent to increasing the signal-to-noise ratio at the input of the device, or increasing noise immunity. Introducing random time delay information to block 6 by connecting the output of discriminator 2 to the input of adder 11 of block 6 is equivalent to increasing the holding band of block 6, which reduces the probability nepeckqKOB in phase and, therefore, further increases the noise immunity of the device. Improving the accuracy of estimating a random time delay is also achieved by using only one controlled generator 13 of block 6, which eliminates errors associated with the non-synchronous operation of controlled generators. In addition, the use of a single controlled oscillator 13 makes it possible to eliminate the need for periodic monitoring of uniqueness, since in this case it is carried out continuously. Block 9 combines adjusted clock and carrier oscillations often containing rough and accurate, but ambiguous, estimates of the random clock, respectively, which significantly improves the accuracy of the final estimate. The outputs of block 6 and the phase shifter present, respectively, the carrier and clock bands, synchronized with pr The signal 14 These oscillations go, respectively, to the first and second inputs of the random time delay estimator 9. Block random time delay works as follows. The oscillation from the output of the controlled oscillator 13 (FIG.) Synchronized with the received signal (FIG. 3C) is fed to the input of a short pulse pulse generator 15, which generates pulses (FIG. 3 (9), whose fronts correspond to points C + kTo, where, 1, 2, .... From the output of the phase shifter 8, the oscillation of the clock frequency (Fig. Sv), which is also synchronized with the received signal, arrives at the strobe driver 16. It generates pulses (Fig. 3g) with a duration equal to the period of the carrier frequency Tjj, the middle of which strictly coincides with the points D (Fig. 3 c) Pulses with the outputs of the strobe driver 16 and the driver of 15 short pulses are fed to the inputs of the coincidence unit 17, from whose output the pulses are removed (Fig. Ze), the temporal position of the fronts which uniquely determines the random time delay of the received signal with an accuracy equal to the accuracy of the unambiguous estimate unit 6. From the output of unit 9, the evaluation of the calculation of the random delay can be used for the operation of other systems, for example, in complex radio communication and radio navigation systems with accurate determination of the current location Yeni mobile unit. The use of the invention in communication systems, radionavigation and radar provides their noise immunity and accuracy of tracking the random time delay of the received signal.

Claims (1)

DEVICE FOR RECEIVING SIGNALS WITH SYNCHRONOUS MANIPULATION, containing a frequency divider, a synchronous detector, the first input of which is combined with the first input of the multiplier and is the input of the device, the second input of the multiplier is connected to one input of the reference signal generator, the other output of which is connected to the first input of the discriminator, the second input which is connected to the output of the synchronous detector, and the output of the multiplier is connected to the first input of the phase locked loop, characterized in that, in order to increase the the stability and accuracy of estimating the random time delay of the signal, a low-pass filter, a phase shifter and a random delay estimation calculating unit are introduced into it, and the discriminator output is connected to the input of the low-pass filter and the second input of the phase-locked loop, the output of which is connected to the second input of the synchronous detector, the first input of the random delay estimate calculation unit and through the frequency healer with the input of the phase shifter, the control input of which is connected to the low-pass filter output, the phase output the rotator is connected to the input of the reference signal generator and the second input of the random delay estimation calculation unit, the output of which is the output of the device. (AND) Figure 1 with 1 469191