SU1730597A1 - Device for measurement of wave length in waveguide - Google Patents

Abstract

The invention relates to a radio measuring technique and can be used to measure the wavelength in a transmission line. The purpose of the invention, the automatization of measurements, is achieved by introducing a reversible electric drive 8 with limit switches 9 and 10, which limit the movement of the reflecting heterogeneity 3 associated with the electric actuator 8. When the heterogeneity 3 is displaced, an alternating voltage is generated at the output of the reflected wave 6 whose frequency is proportional to speed displacement of the inhomogeneity 3 and inversely proportional to the wavelength. Thus, by measuring the frequency using the frequency meter 7, at a known speed of Heterogeneity 3 can determine the desired wavelength. 1 il.

Description

This invention relates to a radio measuring technique.

Devices are known for determining the wavelength in a waveguide.

The disadvantage of these devices is the need to locate the detector probes inside the waveguide volume and to ensure stable connection of the probe with the detector during longitudinal movement of the probe along the waveguide, which leads to a significant error in measuring the wavelength in dielectric and metal-dielectric waveguides.

The closest to the present invention is a device for determining the wavelength in a waveguide, comprising a generator connected in series, a directional coupler, a first reflecting inhomogeneity, having the ability to reciprocate along a waveguide, a second reflecting inhomogeneity, and a detector connected to the output of the secondary channel otvetvitel, and the output - with the indicator.

A disadvantage of the known device is the impossibility of measuring the wavelength in an automated mode.

The purpose of the invention is to automate the measurement of the wavelength in a waveguide.

The goal is achieved by introducing a reversible electric drive connected to the first reflective heterogeneity to the wavelength measuring device in the waveguide, the limit switches installed at the end points of its movement and connected to the inputs of the entered RS flip-flop, the outputs of which are connected to the control inputs of the account electronically - counting frequency meter, which serves as an indicator.

The drawing shows a structural electrical circuit of the device.

A device for measuring wavelength in a waveguide comprises a sequentially connected oscillator 1, a directional coupler 2, a first reflecting discontinuity 3, having the possibility of reciprocating movement along the waveguide 4, and a second reflecting discontinuity 5, as well as a detector 6 connected to the output of the secondary of the channel of the directional coupler 2, and the output with the indicator 7, the reversible electric drive 8 connected to the first reflecting heterogeneity 3, the limit switches 9 and 10, installed at the limit ah its movement and connected to the RS-flip-flop 11 inputs the outputs of which are connected to the inputs upravle-

nor the count of the electron-counting frequency meter 7, which serves as an indicator.

The device works as follows.

The signal from generator 1 through the directional coupler 2 enters the segment of the waveguide 4 under study, where it undergoes reflections from the placement planes of the first and second reflecting inhomogeneities 3 and 5.

The signal at the output of detector 6, taking into account the quadraticity of its characteristic and the weak disturbing effect of inhomogeneities on the field of waveguide 4, has the form

Ug k S2 2 + 2 cos (2 0, + 2% - #). where k is the coefficient taking into account the transient attenuation of the coupler 2, and the transmission coefficient of the detector 6;

S ,, is the modulus of the reflection coefficient of an inhomogeneity of 3 or 5;

, 2jtt yj -JT electric track-8 length between inhomogeneities;

 Phase 2 of the reflection and transmission coefficients of heterogeneity 3 or 5.

The first reflective inhomogeneity 3 is moved by a reversible electric drive 8 at a constant speed V. One of the limit switches 9 or 10 is closed and a read enable signal is received from the output Q or Q of the RS flip-flop 11 to the count control input of the electron-counting frequency meter 7. Taking into account that the distance L along the waveguide 4, by which the first inhomogeneity 3 can move, is many times greater than the maximum possible wavelength in the waveguide Az, as well as the reactive nature of the inhomogeneities 3 and 5, for example, capacitive probes, the signal taken from the detector 6, can be written as

Vg 2k S, (1 + cos V t

where V is the speed of movement of the reflective inhomogeneity 3 along the waveguide 4.

The variable component of the detected signal is

2kS, 2

cos

4tg

IT

v t

and changes with frequency

O -4 / -t-V,

As

determined by the electron-counting frequency meter 7. Then the wavelength in waveguide 4 at a known speed of movement of inhomogeneity 3 is defined as

h 2 v

Compared to the known, the proposed device allows the measurement of the wavelength in the waveguide in an automated manner.

Claims (1)

Apparatus of the Invention A device for measuring a wavelength in a waveguide, comprising a series-connected oscillator, a directional tap, a first reflecting inhomogeneity, having the ability to reciprocate along a waveguide, and a second reflecting inhomogeneity, as well as a detector, input 0 connected to the output of the secondary channel of the directional coupler, and the output to the indicator, characterized in that, in order to automate the measurements, a reversible electric drive connected to the first reflecting inhomogeneity was introduced into it, limit switches installed at the extreme points of its movement and connected to the input entered - a RS flip-flop, the outputs of which are connected to the control inputs of the account of the entered electron-counting frequency meter, which serves as an indicator.