SU700843A1 - Device for determining the sign of phase difference - Google Patents

Description

one

The invention relates to the field of phase measurements and can be used in the construction of noise-proof phase meters.

A device for determining the sign of a phase difference is known.

. The disadvantage of the device is that in the presence of noise, the appearance of false pulses at the output is possible; Former of short pulses E1 - leads to a false setting of the sign trigger and incorrect definition of the sign of the phase difference.

A device for determining the sign of the phase difference is known, which contains input shapers, a shaper of short impulses f keys and a flip-flop sign 2.

Such a device has a low noise immunity.

The purpose of the invention is to improve the resistance to microscopes.

This goal is achieved by the fact that the device containing the first and second input drivers, the driver of short pulses and the sign trigger, is equipped with an additional driver of short pulses of the first and second D-triggers, and the codes of the first and second input drivers through the driver

0 and the additional driver of short pulses are connected respectively to the C-inputs of the second and first D-flip-flops, the D-inputs of which are connected respectively to the outputs of the second and first shapers, and their outputs - respectively to the C- and D inputs of the sign trigger.

FIG. 1 shows a block diagram of the device; in fig. 2, a are given

0 voltage plots, which show his work.

The device contains the first and second input shapers 1 and 2, shaper 3 short pulses and

5 additional clock shaper 4 short pulses, the first and second D-flip-flops 5 and 6, the trigger 7 characters.

The device works as follows.

Input signals, mixed with noise, are fed to the shaper inputs

1 and 2, with the help of which they are converted into rectangular pulses

(Fig. 2a, b). The fronts of these pulses correspond to transitions of the mixture of input signals and noise through the zero level. In the case of a wideband shma, there is a probability of multiple zero intersection of the signal and noise in the region of the signal zero crossing. This leads to the appearance of the formers 1 and

2 complex impulses that disrupt normal operation. Shapers 3

.and 4 short pulses form short pulses (Fig. 2c, d) corresponding to the positive and negative edges formed by the formers 1 and 2. Short pulses arrive at the clock inputs of the B-flip-flops 5 and 6, on the outputs of which a potential is established, corresponding voltage-on the input of the corresponding trigger 5, b (Fig. 2e, e). Trigger. 7.7 tons activated by a positive fraud, performing the FUNCTION of the sign trigger, when connecting its inputs, indicated in FIG. 1 is set to the position (Fig. 2, g) at H 7 O and in polo

at about such an image

In spite of the presence of false pulses at the output of drivers 1 and 2, caused by noise, the proposed: the device allows you to determine the sign of the phase difference of the signals ..

Introduction to the device of two 3) -triggers and an additional short pulse shaper allows to significantly increase its noise immunity, as it provides

determination of the sign of the phase difference in the presence of noise.

The application of the proposed device in overlapping phase meters makes it possible to increase their sensitivity and noise immunity, since one of the main components of such phase meters subject to the action of interference is a device for determining the sign of phase difference. Improving the noise immunity of the phase meter will lead to its expansion.

Claims (2)

1. USSR author's certificate number 469098, cl. GGIT 25/00, 1976. 2. Authors certificate of USSR 0 352230, cl. G01 R 25/00, 1975.