SU828112A1 - Discrete phase-meter - Google Patents

Description

The outputs are to discrete meters of the logarithm of the ratio of voltages 4, and the outputs of the latter to the code conversion unit 5.

The device works as follows.

The input voltages Usj.i Ucoswt and i / gx2 f cos (), the phase difference φf of which must be measured using phase splitter 1, is converted into four pairs of voltages: common mode

11 fy cos with and f / ia f / cos (w g + D p), antiphase

u. ,, Ucos (i +) - f / 22 Ucos (wt + A 9) excellent on / 2

{/ 31 cos (co / + / 2);

32: cos (W + D p),

and excellent on l / 2

  LJcos ((- 1G / 2); cos (co -f D).

Then on adders 2, the voltages Un and t / i2 are added in pairs; / 21 and (722; 3i and f / 32; and t / 4b. Total voltages are applied to quadratic detectors.

At the output of quadratic detectors, the voltages of the low-frequency envelopes are highlighted (Fig. 2a).

U, KU, (l - {- cosL f) U., - KU (l -co8D p)

and, rz: / C (7o (l +)

fU4 / Cf / o (l-sinD p).

Then the voltages f / i and / 2 are applied to a discrete meter of the logarithm of the ratio of these voltages 4. At the output of the meter, a code is formed:

- / h l i, 1 + cos D 9

A (L p) In: In.

 f / 21 - COS D 9

The essential feature of the function X1 (Af) is that it is practically linear on the intervals Dfl; / 2 ± / 4 and Df 3/2 ± / 4. Thus, it is possible to present the results of the measurement of Df as a pair of linear-broken dependencies of discrete codes on the measured phase difference (Fig. 26). As can be seen from FIG. 26, each of the measurements;, 1 (Df) and A, 2 (Df) is ambiguous. To eliminate ambiguity, the signals from the outputs of the logarithms of the ratios are fed to the code conversion unit 5.

In this case, at the output of the code conversion block 5, the dependence S (Df) (Fig. 2c) of codes is formed, linearly varying in proportion to the measured phase difference Df, and an intermediate discrete measurement of the logarithm of the voltage ratio was used to obtain this dependence.

Thus, the device can be significantly simplified by eliminating complex and expensive CRT meters or complex multichannel (by the number of measurement slots) phase splitters.

Measurement accuracy will increase if discrete log-to-voltage ratio meters are used with the number of samples needed to measure phase differences in the range of only ± / 4.

This simplification reduces the cost of manufacture and operation of the device, as well as automates the process of measuring the phase difference and processing the measurement results.

Formula of invention

Claims (2)

1. A discrete phase meter containing a phase splitter of input signals with four pairs of outputs, and on the first pair of outputs both signals are in phase with the input, on the second, one signal is siphasen, the other differs by 180 °, on the third - by –f 90 °, on the fourth - at -90 and each a pair of outputs is connected respectively to the first, second, third and fourth two-input adders, the outputs of which are connected to the first, second, third and fourth quadratic detectors, respectively, characterized in that, in order to reduce the cost of its implementation and improve accuracy, two discrete a voltage ratio logarithm and a code conversion unit, wherein the outputs of the first and second quadratic detectors are connected to the first discrete voltage ratio logarithm, and third and fourth rows quadratic detectors - a second discrete logarithm of the ratio meter voltages thus outputs discrete logarithm ratio gauges are connected to the voltage converting unit codes. 2. Phase meter according to claim 1, characterized in that the discrete meters of the logarithm of the voltage ratio are made with a measuring range of the phase difference within ± / 4. Information sources, taken into account in the examination 1. Japanese patent application No. 49-16835, 110Н2, 1974. 2.Grapkin I.M., Ishchaschad V. A. For a wideband four-detector analyzU phase measuring systems. Lime universities of the USSR "Radioelectronics, 1968, t. XI, 4, p. 332 (prototype). l / fjf -l / ffffS l /.- l / fosi t f I {L f) ./  F kf Y Af L