SU799158A1 - Synchronizing device - Google Patents

Description

54) SYNCHRONIZATION DEVICE

The invention relates to radio engineering and can be used in synchronization systems for receivers of optical signals.

A synchronization device is known comprising a synchronizer, the output of which is connected to the first inputs of the first and second integrators, the outputs of which are connected to the inputs of the first differential amplifier 1.

However, such a device has a low synchronization accuracy.

The purpose of the invention is to improve the synchronization accuracy in the conditions of fluctuations of signal levels and noise.

The goal is achieved by the fact that a synchronization device containing a synchronous generator, the output of which is connected to the first inputs of the first and second integrators, whose outputs are connected to the inputs of the first differential amplifier, is inserted in series a second differential amplifier, two-way limiter, adder, first non-recursive filter and third a difference amplifier, as well as a polarizer, a signal and noise photodetectors, and a second non-recursive filter, while the polarizer outputs are connected to the input m of a signal photodetector and a noise photodetector, the output of which through the second non-recursive filter is connected to the second input of the third differential amplifier, the first input of which is combined with the second inputs of the second differential amplifier and adder, and the output of the third differential amplifier.1niter is connected to the input of the synchronous generator, and the output of the signal The photodetector is connected to the combined second inputs of the first and second integrators.

The drawing shows a structural electrical circuit of the proposed device.

The device contains synchronizer 1, integrators 2 and 3, difference amplifiers 4-6, double-sided limiter 7, adder 8, non-recursive filters 9 and 10, polarizer 11 signal 12 and noise 13 photocelectors.

The synchronization device works as follows.

Claims (1)

The clock signal is a pulsed signal with circular polarization. It arrives at the output of the polarizer 11, from which a signal emission and noise mixture enters the output of the signal photodetector 12, and only noise radiation leaves the output of the noise photodetector 13. From the output of the noise photodetector 13, the signal enters the non-recursive filter 10, in which the average noise value is determined by results there are several samples. At the same time, when recording the value of the next sample, the first one of the previous values is erased and thus the time average value of the noise level slides over time. At the same time, the mixture of signal and noise radiation enters integrators 2 and 3, which gates with the principle of advance-delay gating, therefore the signal at the output of the first difference force of body 4 is proportional to the time shift between the beginning of integration and the beginning of the pulse. If the signal at the output of the first differential amplifier 4 is caused only by slow changes in the temporal position of the signal pulse and there are no anomalous distortions due to changes in the intensity of the received radiation, then in the setting mode the negative feedback from the non-recursive filter 9 to the differential amplifier 5 is compensated positive feedback from the non-recursive filter 9 to the adder 8. As a result, the output value of the difference amplifier 4 is directly fed to the output of the first an italic filter 9 in which sliding averaging occurs over several realizations m. From the output of the non-recursive filter 9, the signal enters the difference amplifier 6, the second output of which receives the result of averaging noise from the non-recursive filter 10. Thus, the resulting signal from the output of the difference amplifier b is proportional to the time shift of the pulse. With fluctuations of signal levels and noise, the output signal of the differential amplifier 4 depends on the absolute fluctuating signal levels and noise. In this case, the signal fluctuations are decisive, which leads to signal distortions. With these distortions, the two-sided limiter 7 significantly reduces them from above and below at the output of the difference amplifier 5. This results in a more reliable signal at the output of the non-recursive filter 9, which, having passed the difference amplifier 6, is fed to the input of the synchro-generator 1 for its adjustment. At the same time, as a result of noise averaging in non-recursive filters 9 and 10, the influence of its fluctuations is reduced, and due to the inclusion of difference amplifier 6, the effect of its absolute level on the accuracy of the synchronization device is reduced. The invention includes a synchronization device comprising a synchronizer, the output of which is connected to the first inputs of the first and second integrators, the outputs of which are connected to the inputs of the first time amplifier, characterized in that, in order to increase the synchronization accuracy in terms of. x fluctuations of signal and noise levels, a second differential amplifier, a double-sided limiter, a first non-recursive filter and a third differential amplifier, as well as a polarizer, a signal and noise photodetectors, and a second non-recursive filter, are introduced in series, while the outputs of the polarizer are connected to the signal inputs photodetector and noise photodetector, the output of which through the second non-recursive filter is connected to the second input of the third differential amplifier, the first input of which is combined with torymi inputs of the second differential amplifier and the adder, and the output of the third differential amplifier connected to the input clock, wherein the output signal of the photodetector is connected to the combined second inputs of the first and second integrators. Sources of information taken into account in the examination 1. Role of PMN P.M., Karp S. Optical communication. I., Sv zb, 1978, p. 340, fig. 10 and b (prototype).