SU1318934A2 - Device for measuring modulus and phase of complex reflectance of microwave two-terminal network - Google Patents

Abstract

Invention m. used in automatic measuring systems and devices built-in controls. The purpose of the invention is to improve the measurement accuracy. The device contains microwave rr-1, a transmission line segment with a sensor probe 2, communication probes 3-6, microwave switch 7, control unit 8, quadratic detector 9, controlled voltage divider 10, band-pass filter 11, linear amplitude detector 12, phase meter 13, phase indicator 14, dividing unit 15, low-pass filter 16, module indicator 17, microwave two-pole 18 under study. Due to the introduction of divider 10, the measured values of the module and phase of the complex coefficient. The microwave two-port network does not depend on the non-identical coefficients. transmissions of probes 3-6, as a result of which the measurement accuracy is the same 1 il. (L SLE 00 with SAE to

Description

The invention relates to a radio measuring technique, may be used. Called in automatic measuring systems and devices built-in control and is an improvement of the device according to the author. St. №1191843

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

The drawing shows the structural electrical circuit of the device for measuring and the phase of the complex reflection coefficient of the microwave two poles.

The device for measuring the module and the phase of the complex reflection coefficient of the microwave two-pole network contains serially connected microwave generator 1, a segment of the transmission line with a four-probe sensor 2, probes 3-6 of the communication of a four-probe sensor 2, microwave switch 7, control unit 8, quadratic detector 9, controllable voltage divider 10, band-pass filter 11, linear amplitude detector 12, phase meter 13, 14 indicator light, dividing unit 15, low-pass filter 16, module indicator 17, microwave two-port 18 under study.

A device for measuring the modulus and phase of the complex reflection coefficient of microwave bi-poles operates as follows.

The output signal of the microwave generator 1 through a segment of the transmission line with a four-probe sensor 2 is fed to the input of the investigated microwave two-terminal 18, characterized by a complex reflection coefficient G.

As a result of interference, incident and reflected waves, there is a field in the segment of the transmission line with four sensors probe 2, the distribution analysis of which is carried out with the help of four probes 3-6 arranged in such a way that the phase incursions between them are equal to 31/4 on the average the wavelength of the working range of the device.

The microwave switch 7, controlled by the control unit 8, alternately connects the outputs of the probes 3 to 6 to the input of the quadratic detector 9. The detected signal at the output of the quadratic detector 9 is a periodic function with a period equal to the switching period of the microwave switch 7. The output amplitude the signal of the quadratic detector 9 depends on the distribution of the field in the segment of the transmission line with the four-probe sensor 2 and the transmission coefficients of the probes 3-6. Managed divider 10 has four divisions according to the number of probes.

3 - 6. The division factors of each

steps are inverse to coefficients in front of the a-chi of the corresponding probes 3-6. The control unit 8 switches the dividing stages of the controlled divider 10

synchronously with the switching of the microwave switch 7, while the amplitude of the output signal of the controlled divider 10 depends only on the distribution of the field in the segment of the transmission line with the four-probe sensor 2 and does not depend on the transmission coefficients of the probes 3-6, Band-pass filter 11 tuned to the switching frequency of the microwave switch 7 and controlled divider 10 allocates

the first harmonic of the output signal of the controlled divider 10. At the same time, the output signal of the controlled divider 10 is fed to the filter 16, which selects a constant component

this signal is proportional to 1 + (g / g.

The output signal of the bandpass filter 11 is fed to the input of a linear amplitude detector 12 and the first

the input of the phase meter 13, the second input of the reference receives the reference voltage from the second output of block 8. The output voltage of the linear amplitude detector 12 is proportional to / g /,

It is fed to the first input of the block 15, to the second input of which the output voltage of the filter 16 is applied, which is proportional to 1 + / G /. At the same time, the output voltage of block 15 is proportional to

nationally

| G /

and not for 1 + / Y / 2

depends on the transmission coefficients of the probes 3–6. The output voltage of the unit 15 is supplied to the indicator 17, programmed in units of the module, and the output voltage of the phase meter 13 is fed to the indicator 14, calibrated in units of the phase of the reflection coefficient of the microwave bipolar 18 under study.

Thus, by introducing a controlled voltage divider iz. The measured values of the module and the phase of the complex microwave multiplex coefficient do not depend on the non-identity of the transmit coefficients of the probes, as a result of which the measurement accuracy is increased. ,

3I31893A4

Claims (1)

Claims carry measurements, output quadratic A device for measuring the detector module is connected to the input of the band phase of the complex coefficient from the fi rst filter through the input of the control of the microwave two-terminal network to the automatic voltage divider controlling St. No. 1191843, distinguishing- “the entrance of which is connected to the first outlet by the fact that, for the purpose of turning the control center point into ..