SU1308932A1 - Phase-meter - Google Patents

Abstract

This invention relates to a measurement technique. The purpose of the invention is to improve measurement accuracy. The phase meter contains transducers 1 and 2 frequencies, a local oscillator 3 phase detector 4, single-side mixers 6 and 7, a tunable generator 8, a control element 10, a delay line 12, and a frequency meter 13. A phase detector 5, a tunable generator 9, and a control Element 11. Due to this, there is no return heterodyne in the phase meter, and the adjustment characteristic is largely linear. 1 il. (Ls

Description

The invention relates to a measurement technique for measuring the phase difference of two electrical oscillations, and can be used in the development of phaseometric devices intended for

various radio devices I

The aim of the invention is to improve the measurement accuracy.

The drawing shows the functional diagram of the phase meter.

The phase meter contains two transducers 1 and 2 frequencies in the reference and information channels with a common heterodyne 3 connected to the inputs of these transducers, the first and second phase detectors 4 and 5, the first inputs of which are connected respectively to the outputs of the transducers 1 and 2, and the second inputs - with the outputs of the first and second single-band mixers 6 and 7, respectively, the first and second tunable generators 8 and 9, the control inputs of which are connected respectively through the first and second control elements 10 and 11 to the outputs of the corresponding gas detectors 4 and 5, a delay line 12 connected between the output of the first tunable generator 8 and the first input of the second single-band mixer 7, the output of the second tunable generator 9 connected to the second inputs of the first and second single-band mixers 6 and 7 directly, and the first input of the first one the band mixer 6 is connected to the output of the first tunable generator 8, which, in turn, is connected to the frequency meter 13. The tunable generators 8 and 9 with the control elements 10 and 11 are made such Braz, that when applying a control signal magnitude and one of naka oscillation frequency generators are changed by the same amount but in opposite directions.

Phase meter works as follows.

Input reference and information signals using transducers 1 and 2 with a common local oscillator 3 are formed in oscillations with an intermediate hour.

this fg, with the measured phase difference 4t | contained in the information input signal, without change, is transferred to the oscillations allocated by the output of the frequency converter 2

in the information canape. The signals from the outputs of converters 1 and 2 frequencies arrive at the first inputs of the first and second phase detectors 4 and 5, respectively, the second inputs of which receive signals from the outputs of single-side mixers 6 and 7, respectively. At the outputs of the mixers, oscillations with the same frequency f ,

f. + f, where f.

, 5 d

and f are the frequencies of the first and second tunable oscillators 8 and 9, respectively.

At the output of phase detectors 4 and 5, control signals appear that, acting on control elements 10 and 11, rearrange the generators 8 and 9 to some frequencies f, and f, the values of which satisfy the following relations: I

f:

+ f:

Where

LO

-9, h-s, H-Cf 4 + -V, +4, tfi -211 f С,

H and h

(one)

2irk; (2)

 cf +, (3)

0

SU, “V,

five

the values of the initial phases of oscillations, respectively, of the first and second generators 8 and 9;

delay time line 12 delay; the initial phases of the oscillations applied respectively to the inputs of converters 1 and 2 ;. CpQ - some phase

a shift depending on the type of phase detectors 4 and 5 used;

 - whole numbers. . From relations (2) and (3), it is found, 5 that the oscillation frequency of the first generator 8 f is equal to

f Li 4- ± 21: ikiai

. one

one

but Cj j - Vi is the measured phase difference bCf. Then the expression (4) takes the form

Oir

(five)

p and

;

(four)

0

five

  I ± 2 ikin}. 1 2. Substituting the expression (5) in the corresponding- (1), get the value of the hour-generator 9

 L E-i TiDiisl

2ir o3

wearing totah f

 fa -ft fo

By measuring using the frequency meter 13 the oscillation frequency of the tunable generator 8, it is possible to determine the magnitude of the measured phase shift uqi.

With changes in the value of the measured phase shift by the value of S DC, the relation (3) is violated. As a result, the output phase de. of the vector 5 appears a control signal, which, acting on the control element 11, changes the oscillation frequency of the generator 9, which, in turn, leads to violation of relations (1) and (2) and the appearance of the control signal at the output of the phase detector 4. This signal tunes the frequency of the generator 8. The described process proceeds until the generators are tuned to new frequencies f and f J which satisfy 1 (1), (2) and (3 ). Based on equations (1), (2) and (3 jf LF +) + 21Г (n-k)

: 5 -. “F.

(6)

u (r. n;: k} 2 --o 2-0-0-3 From expressions (5) and (6) it follows that the frequency of the generator 8 changes by

L f

(

- f

if 21Гс

By measuring using the frequency meter 13 the increment of the frequency of the generator 8, it is possible to determine the magnitude of the change in the phase shift.

There is no return heterodyne in the device, and the non-linearity of the phase-frequency characteristics of the filters included in the single-band mixes 6 and 7 does not matter, since they operate at a strictly fixed frequency fg. Thus, the contributor M. Katanova Editor O. Yurkovetska Tehred L. Oleinik Proofreader S. P1ekmar

Order 1794/37 Circulation 731 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, Projecto st., 4

The adjustment device is substantially linear in comparison with a similar characteristic of a known device, and, consequently, the measurement accuracy of the magnitude of the phase shift Bbmie.

Claims (1)

Invention Formula A phase meter containing two frequency converters in the reference and information channels with a common local oscillator connected to the inputs of these converters, the first and second single-band mixers connected in series the first phase detector, the control element, the first tunable generator, the delay line and the frequency counter which input is connected to the output of the first tunable generator, the output connected to the first input of the first single-band mixer, and the output of the delay line connected to the first input of the second one-band The output of the first single-band mixer is connected to the first input of the first phase detector, differing in that, in order to improve the accuracy of measuring the phase shift, the second connected phase detector, the second control element and the second tunable a generator whose output is connected to the second inputs of the first and second single-band mixers, the outputs of the first and second frequency converters are connected to the first inputs of the first and second, respectively phase detectors, and the second input of the second phase detector is connected to the output of the second single-band mixer.