SU1095094A1 - Two-channel phase meter - Google Patents

Abstract

A TWO-CHANNEL PHASOMETER containing series-connected .51 li. iEli 11Ш, t; Х1Нг: ЕГ / А LIBRARY microwave signal generator, power divider; calibrated; phase shifter and attenuator included in the reference channel, subtraction unit, detector and indicator; the second output of the power divider and the second input of the subtraction unit are connected to the terminals for connecting the unit under study in the measuring channel, so that the measurement range, a modulator connected to the control input of the microwave signal generator, and a recording unit of the multiplicity 360 of the measured phase difference connected to the detector output are entered. (L with with cd about with

Description

The invention relates to a radio measuring technique and can be used in the study of the phase-frequency characteristics of microwave devices and paths. A two-channel phase meter is known, comprising a microwave generator, a power divider, the device under study and an amplitude modulator included in the measuring channel, a calibrated variable; Phaser, including a reference channel, an adder, a detector, and an indicator device With t X The disadvantage of the known device is the narrow measurement limits phase shift. The closest to the invention in its technical essence and the effect achieved is a two-channel phase meter containing a series-connected microwave generator, a power divider, a calibrated phase shifter, and a variable attenuator included in the reference channel, the subtractor unit, the detector and the indicator, the second output of the power divider and The second input of the readout unit is connected to the terminals for connecting the tested unit C 2 3. A disadvantage of the known device is also the narrow limits of the phase shift measurement. The aim of the invention is to expand the phase shift measurement. The goal is achieved by the fact that a dual-channel phase meter containing serially connected microwave generator, power divider, calibrated phase shifter, attenuator included in the reference channel, subtraction unit, detector and indicator, the second output of the power divider and the second input of the detracting unit connected to the terminals for connecting the block under study in the measuring channel, entered a modulator connected to the control input of the microwave signal generator, and a recording unit of the multiplicity 360 of the measured spacer Connected to the output of the detector. The drawing shows the block diagram of the proposed two-channel phase meter. The two-channel phase meter contains a microwave signal generator 1, a modulator 2, a power divider 3, a test block 4, a calibrated phase shifter 5, an attenuator 6, a subtracting block 7, a detector 8, an indicator 9, and a block 10 for recording the 360 ° multiplicity of the measured phase difference. The device works as follows. The signal of the generator 1, modulated in frequency by means of the modulator 2, passes through the power divider 3 and goes to the reference and measurement channels. The signal of the measuring channel passes through the block 4 under study, and the signal of the reference channel passes through a calibrated phase shifter 5 and attenuator 6. After alignment of the signals in phase and amplitude, they are subtracted in subtractive block 7. It is known that the phase shift introduced by the segment of transmission line 6 is calculated by formula U) - 7 1 L. a segment, where K 1, 2, 3 ..., is similar to the formula and / .. 360 C 2 When the wavelength is changed, the phase shift introduced by the segments will change accordingly. , , ZYO; (. .- ,,., Subtracting V from r from 2 + L and bruppling ratio / 1 2 / a V, when we have 2 / lC K. From this it is seen that for changes in the frequency of the signal, the ratio of changes in the phase shifts of the two The lengths of the transmission line of different lengths are proportional to the ratio of the lengths of these lengths. When this happens, at the output of the detector 8, at different phase raids of channels that are not multiples of 360 °, the signal amplitude changes with double frequency (2F) with respect to the law of amplitude change frequency F of the generator 1. The amplitude of the signal with a frequency of 2F is recorded by block 10, on a scale which The number η is shown, which shows how many times 360 ° is contained in the phase shift of the device under investigation. The total phase shift of the device under investigation is determined by the formula i / 2 (j-tf) 4n360% where .j and f, j are the readings of the phase rotator 5, respectively the absence and presence of the block under study

in the measuring channel of the phase meter.

The scale of the block 10 is graduated in the absence of the block 4 under study in the phase meter circuit.

The graduation sequence is as follows.

1. The measuring and reference channels are electrically aligned with the help of a variable calibrated phase shifter 5 according to the minimum indication of indicator 9.

2. The output signals of the measuring and reference channels are amplified in amplitude with the help of an attenuator-15 of 6 according to the zero reading of the indicator 9. At the same time, the readings of block 10 are also equal to zero (calibration point). 3. A discrete calibrated phase shifter is turned on in the measuring channel of the phase meter with the input and phase shifts equal to 360 ° (calibration point). 4. Phaser 5 is set to the position corresponding to the closest minimum reading on indicator 9. 5. The amplitude of the output signals of the measuring and reference channels is amplified by the attenuator 6 according to the zero indication of indicator 9. 6. The reading of the block 10 is recorded. It corresponds.

7-. Instead of a discrete phase shifter with an insertion phase shift of 360 °, a phase shifter with a phase shift of 720 ° is included in the measurement channel (the graduation point

8. Consecutively, the operations of claims. 4 and 5.

9. A block reading is recorded. 10. It matches.

10. In a similar manner, the graduations of the unit 10 are calibrated when inserted into the measuring channel.

phase shifters with a phase shift of 1080, 1440 °, etc. In this case, the readings of block 10, the corresponding, 4, etc., are recorded. Experimental studies of the layout of the proposed phase meter operating in the decimeter wavelength range show that it provides an accurate measurement of the phase shift — no worse than +30. The limits of the measured phase shift are from 1 ° to 2000 ° or more. Experimental studies of the prototype phase meter model show that its limits for measuring the phase shift are from 1 to 180 ° with the same measurement accuracy. The proposed phase meter, in comparison with the prototype, allows measuring the phase shift of the devices under investigation in a wide range and with high accuracy, which is necessary when creating radio interferometers.

Claims (1)

TWO-CHANNEL PHASOMETER, containing serially connected microwave signal generator, power divider; calibrated? a phase shifter and an attenuator included in the reference channel, the subtracting unit, the detector and the indicator, while the second output of the power divider and the second input of the subtracting unit are connected to the terminals for connecting the test unit in the measuring channel, which means that, in order to expand of the measurement range, a modulator connected to the control input of the microwave signal generator and a 360 ° multiplicity registration unit for the measured phase difference connected to the detector output are introduced.