SU363931A1 - PANORAMIC MEASURING GROUP TIME LATE - Google Patents

Description

one

The invention relates to the field of radio engineering measurements.

Panoramic group latency meters are known, including a frequency tunable geyirator, a power splitter, envelope detectors, a phase detector and an indicator.

The disadvantage of these meters is the significant measurement errors caused by the second side component in the spectrum of the amplitude-modulated oscillation.

The purpose of the invention is to reduce measurement errors.

This is achieved by including into the reference and measuring channels between the power splitter and the envelope detectors of two equally waveguide bridges, but the output of a tunable frequency generator is directly connected to the power splitter, one output of which is connected to the reference arm and the other.

The drawing shows the block diagram of the proposed panoramic meter group lag time.

Ou contains a tunable microwave frequency generator /; modulator 2 frequencies; power splitter 3; object 4 measurement; unequal arm waveguide bridges 5 and 5; detectors 7 and S envelope; band amplifiers 9 and 10; phase detector 11; indicator 12 (oscilloscope).

The geoerator / microwave oscillations using a modulator 2 modulate in frequency, for example, according to the sawtooth law. From the output of the measurement object 4, the signal enters the waveguide bridge 5, one of which contains a waveguide delay line creating a delay t. At the bridge output, the signals from both shoulders are folded and using the detector 7 they select the envelope, which after amplification in the band amplifier 9 serves PA phase detector 11.

The reference voltage for the phase detector is generated using a waveguide bridge 6, a detector 7 and a bandpass amplifier (. This method of obtaining a reference signal eliminates the effect of frequency instability on measurement results.

The output nanowire of the phase detector AND is indicated by an oscilloscope 12. The horizontal sweep is synchronized with a voltage modulating the frequency of the microwave generator. The vertical deviation of the oscilloscope beam is proportional to the voltage coming from the phase detector, i.e., Aq: magnitude, and horizontal - to the frequency change 0) (.

It can be shown that the magnitude (s) g) is f (), and the frequencies mr and sg are different by the magnitude of the intermediate frequency at which the signal is amplified by amplifiers 9

ASOT

where is Aft) -

and 10 and which is

frequency deviation, T is the duration of the forward stroke of the sawtooth modulating voltage.

Thus, the magnitude of the soil latency is, by definition, equal to

t () - p {"/ -O

AZ

f-

D-f

is like

and is displayed on the screen

and

The oscilloscope is NOT dependent on frequency.

Subject invention

A panoramic soil lag time meter comprising a frequency tunable generator, a power splitter, envelope detectors, a phase detector and an indicator, characterized in that, in order to reduce measurement, between the power splitter and the envelope detectors, two non-equalized bridges are added to the reference and measurement channels , with the output of a non-frequency adjustable generator directly connected to a power splitter, one output of which is connected to the measured object y, and - bridge to neravnonlechemu onornogo channel.