SU1617393A1 - Doppler meter of speed - Google Patents

Abstract

The invention relates to radar measurement technology and can be used to remotely measure the speeds of moving objects, in particular, to measure the surface velocity of water flow in rivers and canals. The purpose of the invention is to simplify the Doppler velocity meter by eliminating a tracking filter with a signal search circuit. The Doppler velocity meter contains a microwave transceiver 1, a tunable band-pass filter 2, a switch 3, a timer 4, a frequency meter 5, a control unit 6, an indicator 7, a transmit-receive antenna 8, a circulator 9, a microwave generator 10, a receiver 11. by forming a search ring and tracking the Doppler frequency, consisting of a tunable bandpass filter 2, switch 3, timer 4, control unit 6 and frequency meter 5. Turning on frequency meter 5 allows presetting the polo filter 2 to the center frequency of the useful signal spectrum, and then ensure that the tunable band-pass filter 2 tracks the Doppler frequency through the feedback circuit. 1 il.

Description

UNION OF ADVISORS

SOCIALIST

REPUBLIC »sy i» 1617393 A1

STATE NOMINATION

BY INVENTIONS AND DISCOVERIES

AT GNST USSR

DESCRIPTION OF THE INVENTION

K A SECOND CERTIFICATE

$ (21) 4641971/09 (22) 25.01.89 (46). 30.12.90. Bull. No. 48 (71) State Hydrological Institute (72) B.E. Vasiliev, G, S, Klein,

A.N., Chizhov and G, A. Yufit (53) 621.396.96 (088.8) (56) G. Tuzov Isolation and processing of information in Doppler systems, M ,; Soviet radio, 1967, p. 236, (54) DOPPLER MEASURER. SPEEDS (57) The invention relates to radar measuring equipment and can be used for remote measurement of the speeds of moving objects, in particular for measuring the surface velocity of water flow in rivers and channels. The purpose of the invention is the simplification of the Doppler speed meter by eliminating the servo filter with a signal search circuit, the Doppler speed meter contains a microwave transceiver 1, tunable bandpass filter 2, switch 3, timer 4, frequency meter 5, control unit 6 _f indicator 7, transceiver antenna 8, circulator 9, microwave generator 10, receiver 11. The goal is achieved by forming a search ring and tracking the Doppler frequency, consisting of a tunable band-pass filter 2, 'switch 3, timer 4, directs the meter unit 6 and 5 frequency. Turning on the frequency meter 5 allows you to pre-tune the bandpass filter 2 to the * center frequency of the useful signal spectrum, and then provide the feedback of the tunable bandpass filter 2 for changes in the Doppler frequency, 1 ill.

1617393 A

The invention relates to a radar measuring technique: can be used for remote: measuring the speeds of moving objects, in particular, for measuring the surface velocity of water flow in rivers or channels,

The purpose of the invention is to simplify the design of the Doppler velocity measurement by eliminating the tracking filter with a signal search circuit.

The drawing shows a structural electrical diagram of the proposed 15 Doppler speed meter.

The Doppler speed meter contains a microwave transceiver 1 ,. >

tunable bandpass filter 2, switch 3, timer 4, frequency meter 5, control unit 6, indicator 7, transceiver, antenna 8, circulator 9, microwave generator 10, receiver 11,

Doppler speed meter 25 operates as follows.

To measure the flow velocity, the Doppler speed meter is fixedly mounted on a tripod, for example, at the edge of the bridge over the river, jq channel, the transceiver antenna 8 is directed to the water surface and the power is turned on. At the same time, a signal with a frequency from a microwave generator 10 passes through a circulator 9 to an antenna 8, and a moving water surface is irradiated with it, from which a reflected signal with a frequency f ₀ + fa is supplied to the antenna> well. The received signal through the circulator 9 is fed to the input of the receiver 11, which also receives the signal from the microwave generator 10.

At the output of the receiver 11, a signal is generated with a frequency that enters the tunable band-pass filter 45 2. Band-pass filter 2 to the beginning. This moment may not be tuned to the frequency f “. For initial setup, start timer 4, which connects the output of switch 3 for 3-5 s to the input of the receiver. The feedback circuit through the control unit b is an automatic, coarse tuning to the frequency f ^. After 3-5 s, timer 4 is connected via switch 3, the input of the frequency meter 5 to the output of the tunable bandpass filter 2. At the same time, through the feedback circuit, through blocks 5 and 6, the filter 2 is finely tuned to the Doppler frequency f ^.

Thus, along the indicated circuit, the frequency fq is monitored, which is measured in the 5 ^tf 4acTOTbi meter, and the measured frequency value, multiplied by a constant coupling coefficient of this frequency with the water flow rate, is displayed on indicator 7.

Claims (1)

Claim A Doppler speed meter containing a microwave transceiver, to the output of which is connected an input of a bandpass filter, a switch, a control unit and series-connected frequency meter and indicator, characterized in that, in order to simplify the meter by eliminating the tracking filter with a signal search circuit, a timer is introduced the output of which is connected to the switching input of the switch, while the first signal input of the switch is connected to the output of the bandpass filter, the second signal input of the switch I connected to the output of the receiver of the microwave transceiver, and an output switch connected to the input of frequency meter, wherein the bandpass filter is designed as a tunable bandpass filter, whose control input via a control unit connected to the second output of the frequency meter.