SU1357872A1 - Device for measuring resonance system quality factor - Google Patents

Abstract

The invention can be used to measure the electromagnetic properties of substances at high and ultrahigh frequencies. The purpose of the invention is to expand the range of functionality of the device. The device contains a carrier frequency generator 1, modulating generators 2 and 3, a frequency meter 4, a circulator 5, a switch 7, an amplitude detector 8, selective amplifiers 10 and 12, phase-sensitive detectors 11 and 13, and a recording unit 14. Introduction of a phase-sensitive detector 9 and the formation of new functional connections allow one to measure the intrinsic quality factor of the reflection resonant system 6. 1 Il. (D (L OQ EL 00 KD

Description

The invention relates to a technique of radio measurements and can be used, for example, in measurements of the electromagnetic properties of substances at high and ultrahigh frequencies.

The purpose of the invention is to expand the range of functionality of the device by measuring the intrinsic quality factor of a reflective resonant system.

The drawing is a diagram of the proposed device.

The device contains a carrier frequency generator 1, the first 2 and second 3

modulating oscillators and frequency meter 4 connected to generator 1, circulator 5, investigated resonant system 6 connected to one output of the circulator 5, switch 7 connected by one input to the second

the output of the circulator 5, and the second - the second output of the resonant system 6, the amplitude detector 8, the input of which is connected to one output of the switch 7, the third phase-sensitive detector 9, one input of which is connected to the second output of the switch 7, and the second to the generator 1 , the second selective amplifier 10, which is connected by one input to the amplitude detector 8, and the second input is connected to phase-sensitive

detector 9, the second phase-sensitive detector 11, the second input of which is connected to the first modulating generator 2, the first selective amplifier 12, the first phase-sensitive detector 13 which is connected to the modulating generator 3 by the second input, and magnitude and polarity

to generator 1, and the recording unit 14.

The device works as follows.

The frequency of the tunable frequency generator 1 is modulated with the help of oscillators 2 and 3, the frequencies of which W and fl are respectively set far relative to each other, namely) it ji. The signal of generator 1 goes through the circulator 5 to the resonant system 6. The frequency dependence of the reflection and transmission coefficients of the resonant system causes the amplitude modulation of the reflection of the resonance system of the contained and passed through the resonant circuit two modulating oscillators and a system of signals. The signal passed through the frequency meter, connected to the generator-resonant system, is fed to one RF carrier frequency, the output of which is the input of the switch 7 and, when appropriate, is connected to a circulator connected

five

the switch position is detected by the amplitude detector 8, the signal reflected by the resonant system using the circulator 5 is fed to the second input of switch 7 and depending on the position of the switch is detected by the phase-sensitive detector 9, the reference signal to which is supplied from generator 1, or by the amplitude detector 8, and then amplified by the selective amplifier 10. The phase of the signal in the reference channel of the detector 9 is determined by the coincidence of the frequency of the signal from the generator 1 with the resonant frequency of the resonant si system 6 with a shift relative to the phase of the input signal of the detector 9 at an angle o // 2. The selective amplifier 10 extracts from the signal spectrum the components with frequencies y, W ± fl. The received signal is detected by a phase-sensitive detector 11, to which a reference signal from generator 2 is supplied. From detector 11, a signal is sent to a selective amplifier 12 tuned to a frequency I, and then to a phase-sensitive detector 13, the reference signal to which is supplied from generator 3. Detector output signal 13 is recorded using block 14. When the average frequency of the generator 1 coincides with the frequency fрр corresponding to the inflection point of the frequency dependence under study, the readings of the recording unit 14 accept zero e value When the deviation of the average frequency of the generator0

five

0

ra 1 from frequency f

sir

at the output of the phase-sensitive detector 13, in which are determined by the magnitude and sign of the frequency deviation. The signal from the output of the detector 13 is fed in the appropriate polarity to the element controlling the frequency of the oscillator 1, as a result of which the average frequency of the oscillator 1 is automatically tuned to the frequency.

The frequency of generator 1 is measured by a frequency meter 4,

Claims (1)

The invention The device for measuring the goodness of the resonant system under study, a switch, an amplitude detector and a series-connected first selective amplifier and a phase-sensitive detector, the second input of which is connected to the second modulating generator, the second selective amplifier, the second phase-sensitive detector, the second input of which is connected to the first modulating generator, the first output is connected to the registering unit, and the second output - to the carrier frequency generator, other than In order to expand functional capabilities by measuring your own Or O. Golovach 5994/45 Compiled by V.Stukan Tehred A. Kravchuk Co Po Circulation 730 BNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 the Q-factor of a reflective resonant system, a third phase-sensitive detector is inserted in it, which is connected by one input to the first output of the switch, another input is connected to a carrier frequency generator, and the output is connected to the second selective amplifier, while the second circulator output is connected to one switch input, the other the input of which is connected to the second output of the resonant system, the second output of the switch is connected to the amplitude detector, the output of which is connected to the second input of the second selective amplifier. Proofreader M.Sharoshi Subscription