SU1599796A1 - Method of measuring phase difference - Google Patents

Abstract

The invention relates to a measurement technique in the millimeter range, in particular to methods for measuring the relative phase difference of two waves, and can be used for particularly accurate measurements and for the metrological calibration of phase difference meters. The aim of the invention is to significantly improve the accuracy of measuring the phase difference. To measure the phase difference in the transmission line, the reference and test waves are excited and the initial phase shift in the wave under study is determined by the offset of the minima of the interference pattern in the line, and the wave under study is excited with orthogonal polarization and in the same direction as the reference wave. A device for carrying out the method comprises horn exciters 2 and 5, a directional coupler 3, a millimeter-wave generator 4, a dielectric waveguide 6, a device introducing a measurement shift of the initial phase 7, and a matched load 8 and 9. 2 sludge.

Description

one

(21) 4478477 / 24-21

(22) 08.16.88

(46) 15.10.90. Bul Number 38

(71) Institute of Radio Aieiki and Electronics, AI USSR

(72) A.P. Evdokimov, V.I. Kryzhanovsky, -S.A.Provalov and V.P.Shestopapov

(53) 621.317.77 (088.8)

(56) Harvey A.F. Technique of ultra-high frequencies, - M.: Sov.radio, 1965, vol. 1, p. 237.

(54) METHOD OF MEASURING THE DIFFERENCE OF PHASES (57) The invention relates to the measurement technique in the millimeter range, in particular, to methods of measuring the relative phase difference between two waves, and can be used for particularly accurate measurements and for metrological calibration of phase difference meters.

The aim of the invention is to substantially increase the accuracy of the measurement of the phase difference. To measure the phase difference in the transmission line, the reference and test waves are excited and the initial phase shift in the wave under study is determined by the offset of the minima of the interference pattern in the line, and the wave under study is excited with orthogonal polarization and in the same direction as the reference wave. A device for carrying out the method comprises horn exciters 2 and 5, a directional {coupler 3, a millimeter wave generator 4, a dielectric waveguide 6, a device BOj introducing a measuring shift of the initial phase 7, a matched load 8 and a probe 9. 2 Il.

and

(L

at

rvx

at

L

2

/

/

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SP

with

with

vl

with

B5

7

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FIG. i

The invention relates to phase metering and can be applied in laboratories. ; tori conditions for particularly precise

i measurements of phase difference and measuring lines.

The purpose of the invention is to improve the accuracy of measurement of the phase difference,

The method consists in the fact that the transmission lines are driven by the reference and inspected waves, the zones are recorded, the interference pattern is entered, and the initial shift is measured: into the wave being studied, for the second time; The interference pattern is riated and I determine the shift of the initial phase by the H ™ minima of the second interference pattern with respect to the first one, the wave under investigation being eroded on orthogonal polarization and in the same direction with the reference wave. The determination of the measured phase shift is carried out according to the formula

Lf

2j L

d Z,

where JZ is the minimum coordinate offset;

L is the period of the interference pattern.

FIG. 1 shows the setup diagram, and FIG. 2 shows the interference patterns of two waves before the measured shift of the initial phase into the studied wave and after it.

As a transmission line (AIG.): The dielectric wave guide Giz of polyethylene (2.25) of elliptical cross section was selected. The major and minor axes of the cross section ellipse are 4.4 and 2.2 mm, respectively. At wavelength Я 5.8 mm, the deceleration coefficient of the wave is NOT U, 1.10, and the deceleration coefficient of the wave is NOT „U I, 67. The interference pattern period is L 86 m m. Dielectric waveguide 1 is connected to a horn: causative agent 2 waves NOT which; connected to one of the outputs of the power splitter on the directional coupler 3, connected to the output of the generator 4 millimeter waves. To the second output of the power divider on the directional coupler 3, a horn exciter 5 of the HE wave is connected in the dielectric waveguide 6, which is identical to the waveguide 1. The dielectric waveguide 6 passes through the device 7, input the 1599796

ten

J5

the measured primary phase shift, and then the waveguide 6 is located in the immediate vicinity of the waveguide

I at a distance --- from, it is the causative agent of the wave NOT in waveguide 1. The closely spaced segments of waveguide 1 and waveguide 6 are essentially a directional coupler. At the end of the dielectric waveguide 1 there is a matched load 8. In the immediate vicinity of the waveguide 1 at a distance pi

25

0

five

0

five

0

a probe 9 is installed that can be displaced parallel to the axis of the dielectric waveguide and in the plane perpendicular to the latter.

Generator 4 millimeter waves through the power divider on the directional coupler 3 and the horn exciter 2 excite the reference wave NOT, in the dielectric waveguide 1. Part of the generator power 4 through the directional coupler 3 enters the root exciter 5. Waves in the dielectric waveguide 6. Ustr:: —stance 7 makes it possible to introduce a measured shift of the initial phase into the HE-wave in waveguide 6. Next, the waveguide 6 enters into a direct electrodynamic distributed connection with waveguide 1 and excites the wave under study NOT y ,,, yuschuyus propagates in the same direction with the wave NO. The polarizations of the waves are NOT and NOT JI orthogonal to each other.

The probe 9 register the interference pattern in the waveguide 1 (figure 2, solid line). Using a device 7, for example, a metal plate close to the waveguide 6, the measured shift of the initial phase is introduced into the wave under study. The probe 9 registers the interference pattern for the second time (FIG. 2, dashed line) and determines the shift of the initial phase by shifting the uZ minima of the second interference pattern relative to the first

fiZ

.-2J 86mm

mm

55 0.534 happy 33.5 °.

Claims (1)

Invention Formula The method of measuring the phase difference is that in the line 51599796 The transmissions excite the reference and investigated waves, record their interference pattern, introduce the measured initial phase shift into the studied wave, record the interference KapTvmy for the second time and determine the initial phase shift by shifting the minima of the second interference 0.8 0.6 OL 0.2  160 180 200 220 FIG. 2 Editor L.Pcholinsk Compiled by A.Orlov Tehred L.Oliyyyk Order 3141 Circulation 551 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 the picture is relative to the first one, characterized in that, in order to increase the measurement accuracy, the wave under study is excited by a wave propagating in the same direction with the reference wave and on orthogonal polarization. N 1 86mm  2 mm Corrector G.Cherni Subscription