SU1370599A1 - Device for measuring phase difference - Google Patents

Description

(21) 4128693 / 2A-21

(22) 06.20.86

(46) 01/30/88, Bull. № 4

(71) Kharkiv Aviation Institute. N.E. Zhukovsky

(72) E.G.Rolesnik and V.L. The Forty Cop

(53) 621 .317.77 (088.8)

(56) USSR Copyright Certificate No. 983573, cl. G 01 R 25/00, 1980.

USSR Author's Certificate No. 1000931, cl. G 01 R 23/00, 1980.

(54) DEVICE FOR MEASURING DIFFERENCE PHASES

(57) The invention serves to measure the phase shifts of electrical oscillations. The purpose of the invention is to increase the accuracy of measuring the phase difference.

The device contains transducers 1 and 2 frequencies in the reference and information channels, the local oscillator 3, single-pole mixers (C) 4-7 and broadband amplifier 8. C 4 and 5 are identical in the form of analog multipliers 9 and 10 and high-pass filters 11 and 12 respectively . C 6 consists of an analog multiplier 13 and a notch filter I4. The functional connection of the wideband amplifier 8 and C 6 and 7 eliminates the influence of the parasitic components of the frequency converters 1 and 2 and the non-linearity of converting the phase shift to the information parameter — the oscillation frequency. I il.

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with

11370599

The invention relates to a measurement technique related to the measurement of the phase shifts of electrical oscillations, and can be used in the development of phase meters intended for various radio engineering systems.

The purpose of the invention is to improve the accuracy of measuring the phase difference by eliminating the influence of the parasitic components of the transducer signals and and by eliminating the non-linearity of converting the phase shift to the information parameter — the oscillation frequency.

The drawing shows a block diagram of the device.

A device for measuring the phase difference contains two transducers 1 and 2 frequencies in the reference and information channels with a common local oscillator 3, four single-pole mixers 4-7 and a broadband amplifier 8, the output of which is connected to the first inputs of the first 4, second 5 and third 6 mixers . The outputs of converters 1 and 2 in the reference and information channels are connected to the second inputs of mixers 4 and 5, respectively, and the output of the second mixer 5 is connected to the second input of the third mixer 6. Moreover, the output of the third mixer is connected to the first input of the fourth mixer 7, the output of which is connected to the input broadband amplifier 8, and the output of the first mixer 4 is connected to the second input of the mixer 7. The mixers 4 and 5 are identical, i.e. they contain analog multipliers 9, 10 and P and 12 high-pass filters, the parameters of which are the same. In this case, at the output of filters 11 and 12, oscillations with

by frequency

and;

UJ, + s

U), the value of the frequency of the signal at the output of the broadband amplifier 8;

the frequency value of the signal at the second inputs of mixers 4 and 5.

go

At the outlet of the mixer 6, consisting of a series-connected

analog multiplier 13 and rejector filter 14, which suppresses oscillations with a frequency, a signal with a frequency

U)

is allocated

 s 2 uj mixer

, + w, 7 signal

and uJj- tJj,

0

five

0

five

0

five

0

five

0

five

The device works as follows.

Input reference and informational signals using transducers

1 and 2 frequencies with common local oscillator 3 are converted into oscillations with intermediate frequency Wj and the measured phase difference σ contained in the information input signal is transferred without changes to the oscillations allocated at the output of the converter

2 frequencies in the information channel. These signals arrive at the second inputs of the first 4 and second 5 mixers. At the same time, the output of the wideband amplifier 8 generates signal fluctuations, which are fed to the first inputs of mixers 4-6, and then transformed into mixers 4-7, the fluctuations are fed to the input of wideband amplifier 8. Thus, the amplifier 8 is covered by a reverse circuit connection. The input of which is the first inputs of the mixers 4-6, the output of the output of the mixer 7. The amplifier 8 with a feedback circuit forms a self-oscillating system in which, when the conditions of phase and amplitude balance are fulfilled, oscillations with frequency U) depending on the measurement phase shift alf. The measured frequency co, at the output of the amplifier 8, is judged on the magnitude of the phase shift.

Claims (1)

Invention Formula A device for measuring phase difference, containing two frequency converters in the reference and information channels with a common local oscillator, four single-pole mixers, a broadband amplifier whose output is connected to the first input of the second mixer, and the outputs of the frequency converters in the reference and information channels are connected to the second one the inputs of the first and second mixers, and the output of the second mixer is connected to the first input of the third mixer, characterized in that, in order to increase the point 311370599 the first input of the fourth mixer, between the broadband output of which is connected to the input of the broker and the second input of the first and rockband amplifier, and the output of the first input of the third mixer, the second mixer is connected to the second output The third mixer is connected to the input of the fourth mixer.