SU500570A1 - Device for converting input signal in synchronization systems - Google Patents

Description

(54) DEVICE FOR TRANSFORMING INPUT SIGNAL IN SYNCHRONIZATION SYSTEMS

one

The invention relates to the generation of electrical oscillations and can be used in discrete systems of radio communication and radio telemetry.

Devices are known for converting an input signal in synchronization systems of receivers of discrete information, comprising a sequentially connected driver, filter, and doubler. However, the noise immunity under conditions of high level of impulse noise in the communication channel is weak.

The purpose of the invention is to improve the noise immunity of the allocation of clock signals. This is achieved by the fact that a delay element and a subtractor are connected to the doubler output, the second input of which is connected to the doubler output.

FIG. 1 is a block diagram of the device described; in fig. 2 and 3 - temporary

diagrams of his work.

The input device (see Fig. 1) is connected to the input of the input matched filter. 1, the output of which is connected to the input of the unit 2. The output of the doubler 2 is connected to

I inputs of the delay element 3 and read 4. The output of the delay element 3 is connected to the second input of the reader. 4. The output of the subtractor 4 is connected to the output of the device.

FIG. 2a shows the initial binary information. The output voltage of matched filter 1 is shown in FIG. 26. This voltage is fed to the input of doubler 2. The voltage from the output of doubler 2 (see Fig. 2c) progresses element 3 to delay half the clock frequency period. The delayed voltage is represented in FIG. 2g. The voltage from the output and input of the delay element 3 is applied to the calculation of the stele 4. The difference signal is on v; the course of the subtractor 4 is shown in FIG. 2d This signal can be used for narrowband filtering of the clock frequency, since the phase of the first clock frequency in it remains unchanged for any code combinations, which is: but from a comparison of the output signal (see Fig. 2d) with sinusoidal | Clock frequency (see Fig. 2a). As a narrowband filter, either a resonant device or a system / phase locked loop can be used. In the case of using the FAGTCH system or an impulse-phase autosampling frequency for adjusting the phase and using the inclined sections shown in FIG. 2d bold lines, as they give a good sampling characteristic. With accurate phasing of local impulses (see Fig. 2c) of the clock frequency, relative to the incoming information, these pulses fall into the reference signal areas (see Fig. 2g), where the voltage is zero. When the phase of the local pulses is shifted to the left or right relative to the information, a positive or negative voltage appears, respectively, whose magnitude is proportional to the magnitude of the phase misalignment. The device works well not only by the video signal, but also by the radio signal transmitted in the case of binary information by the method of phase shift keying. It does not require the allocation of the reference (vk

Claims (1)

FIG. 1 soky) frequency signal. To do this, it is enough to put a matched radio filter instead of a matched video filter. The temporal relationships for this case are presented in FIG. 3, where in FIG. The input radio signal with phase manipulation is shown behind, FIG. 36 — the voltage at the output of the matched radio filter and in FIG. 3 V - output doubler voltage. This voltage replicates the voltage in FIG. 2c. Apparatus of the invention for converting an input signal in synchronization systems of discrete information receivers operating in channels with a high level of interference, containing an input filter and a doubler connected in series, characterized in that, in order to improve the noise stability of the clock signal, a delay element is connected to the doubler output. and the subtractor, the second input of which is connected to the output of the doubler.