RU2502083C1 - Method of calibrating and checking doppler wind profile radar - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: Doppler wind profile radar emits a signal with a defined frequency to a signal retransmitting device in which Doppler frequency shift of the received signal is performed; the signal with the adjusted frequency is then retransmitted to the Doppler wind profile radar and the speed and height calibration result is obtained by direct measurement. The Doppler wind profile radar and the signal retransmitting device are immovably mounted at different fixed distances from each other, and Doppler frequency of the retransmitted signal is changed in the signal retransmitting device based on a control signal in the interval between arbitrarily fixed positions of the Doppler wind profile radar.

EFFECT: solving the task of calibrating and checking a Doppler wind profile radar using modern devices.

2 dwg

Description

The present invention relates to methods for calibrating and calibrating meteorological instruments using a Doppler radar to determine wind speed and direction, used both for the needs of the national economy and for military purposes, for example, in artillery.

Currently, a complex has been developed for probeless determination of atmospheric parameters using a Doppler radar, but there are no methods for calibrating and checking such complexes.

The authors were faced with the task of developing a method for calibrating and verifying the Doppler radar of wind profiles with the result of direct measurement.

This problem is solved due to the fact that a signal of a certain frequency is emitted from the Doppler radar of the wind profiles to a signal re-emission device in which the Doppler frequency shift of the received signal is produced, then the corrected frequency signal is re-emitted to the Doppler radar of the wind profiles and receive the calibration result by speed and height by direct measurement, while the Doppler radar profile of the wind and the device re-emission of the signal are stationary at various fixed distances niyah from each other, and the change in Doppler frequency reradiated signal to produce device control signal for reradiation signal between fixed positions conditionally of Doppler radar wind profiles.

The technical result of the proposed method is to solve the problem of calibration and verification of the Doppler radar profile of the wind using modern devices.

The inventive method has a combination of essential features not known from the prior art for methods of this purpose, which allows us to conclude that the criterion of "novelty" for the invention.

The inventive method, according to the applicant and the authors, meets the criterion of "inventive step", because for specialists, it does not explicitly follow from the prior art, i.e. not known from available sources of scientific, technical and patent information at the filing date.

The invention is illustrated using the drawings, where

- figure 1 shows a block diagram of an implementation of the method;

- figure 2 is a diagram of the projection of the wind speed vector.

When measuring wind parameters with a Doppler radar profile of the wind (DRPV), the probing microwave signal is directed into space at a certain angle β to the horizon. In this case, atmospheric sounding in one measurement cycle is carried out at azimuthal angles α _N (for example: 0 °, 30 °, 60 °, 90 °, 120 °, 150 °, 180 °, 210 °, 240 °, 270 °, 300 °, 330 °), which are stopped at the time of sounding of the ADF (pie chart method). The wind speed at each stop is calculated by the formula:

F _dN - Doppler frequency of the microwave signal reflected from meteorological atmospheres;

λ is the wavelength of the probe microwave signal;

α _N - azimuthal angles at which atmospheric sounding is performed;

α _in - the angle of the wind speed relative to the north direction;

β is the elevation angle at which sounding of the atmosphere is carried out (given by the design for the ADF; cosβ = const).

The discreteness of the heights at which the wind speed values are given is determined by the duration of the probe pulse τ and is equal to

c is the speed of light.

When calibrating and (or) checking the DRF 1, set it so as to direct the probing microwave signal parallel to the ground to a special signal reemission device 2 (OPS) located at a fixed distance L from the DRF. In this case, the UPS reradiates the incident microwave signal with a Doppler frequency shift corresponding to the microwave signal when it is reflected from meteorological events moving at a certain speed. Receiving this signal, the ADF generates a wind speed value that corresponds to the Doppler frequency shift specified in the UPS at a height (H = Lsin β) corresponding to a given (fixed) distance L.

With this method, the UPS produces a set of re-emitted frequencies with a Doppler shift: ± F; ± 0.707 F; ± 0.5 F; 0, in accordance with the azimuthal angles 0 °, 180 °; 30 °, 150 °, 210 °, 330 °; 60 °, 120 °, 240 °, 300 °; 90 °, 270 °, which simulate the stop of the DRPV when sensing the atmosphere (the DRP does not rotate at the same time).

Since in this method _a α = 0 (probing microwave signal is directed directly at UPS), the formula (1) becomes:

Thus, by setting various HIPS F _dN and conditionally halting DRPS at respective angles α _N, V is checked _in the measurement accuracy, a placing DRPS and HIPS at different distances from each other, verified by measuring the height accuracy at which the speed measured V _in.

Since 3 Doppler frequencies obtained from 3 directions are sufficient to measure wind speed and direction of the wind by the “pie chart” method, four Doppler frequencies re-emitted by OOPS are sufficient for calibrating the DRF, namely ± F and ± 0.5 F. Using these Doppler frequencies, they imitate the microwave signal reflected from inhomogeneities of the atmosphere, coming from 6 directions, namely:

- from the direction 0 ° - + F;

- from the direction of 60 ° - +0.5 F;

- from the direction of 120 ° - minus 0.5 F;

- from the direction of 180 ° - minus F;

- from the direction of 240 ° - minus 0.5 F;

- from the direction of 300 ° - +0.5 F, which follows from figure 2.

This method is carried out according to the test program of operation of the DRF with synchronous control of the device for re-emission of signals with the work of the DRF.

Observing on the screen of the control and information display unit (БУОИ - not shown in the diagram), which is part of the DRPV, the conditional position of the DRPV is given a command (visually or by radio) to switch the Doppler frequency by the UPS device at the corresponding moment in time - between the conditionally fixed DRV provisions.

After the end of the measurement cycle, the DRP produces the values:

- wind speed corresponding to frequency F;

- the height at which the wind speed was "measured", H = L sinβ;

- direction of wind speed depending on the initial position of the DRPV set by the program (the direction of wind speed is not calibrated).

The applicant company has developed design documentation that implements the proposed method of calibration and verification. The practical use of the proposed method is not in doubt, because there is no need to develop complex devices for implementation, which allows us to conclude that the criterion of "industrial applicability" for the invention is met.

Claims (1)

A method for calibrating and verifying the Doppler radar profiles of the wind, characterized in that a Doppler radar profiles of the wind emit a signal of a certain frequency to the signal re-emitting device, which produce a Doppler frequency shift of the received signal corresponding to the signal when it is reflected from the weather, then re-emit the signal with the produced Doppler frequency shift to the Doppler radar profile of the wind and get the calibration result for wind speed in accordance with doppler the frequency shift specified in the signal re-emission device and the height at which the wind speed was measured in accordance with the formula Н = L sinβ, where β is the elevation angle under which sounding of the atmosphere is performed, L is the fixed distance between the signal re-emission device and Doppler a radar profile of the wind, while the Doppler radar profile of the wind and the device re-emission of the signal is stationary at various fixed distances from each other, and the change in the Doppler frequency per the emitted signal produced in the apparatus by the control signal reradiation signal between fixed positions conditionally of Doppler radar wind profiles.

Images