Estimation method of wind velocity of echoes of wind field of low-altitude wind shear of airborne radar

Abstract

The invention provides an estimation method of the wind velocity of the echoes of the wind field of the low-altitude wind shear of an airborne radar. According to the estimation method of the invention, white noises are subjected to modeling by a p-order all-pole filter, so that wind shear radar echo signals are generated; the autocorrelation coefficient of the low-altitude wind shear radar echo signals is calculated; the coefficient of an autoregressive model is calculated, so that a wind shear radar echo power spectrum is obtained; the pole of an equation is calculated; a velocity corresponding to the pole is obtained; and the velocity of the pole is judged, so that power and an average wind velocity can be outputted. The calculation amount of the method of the invention is small. With the estimation method adopted, the limitations of previous schemes are eliminated; clutter filtering is not needed; the accuracy of wind field echoes can be ensured; a condition that the pole drifts tothe direction of ground clutters can be avoided, and therefore, results are more accurate; simulation results can easily verify that the wind velocity estimation method provided by the present invention can reflect actual wind velocities, is effective and reliable, and is suitable for wind shear signal processing under turbulent flow conditions and strong ground clutter conditions.

Description

technical field [0001] The invention relates to the technical field of radar signal processing, in particular to the research on a signal estimation method, especially the wind speed estimation of echo. Background technique [0002] Wind shear is an atmospheric phenomenon, which is a kind of atmospheric turbulence in which the wind direction and speed change suddenly in the horizontal and vertical directions. It is mainly caused by changes in the atmospheric movement itself, and it is also caused by geographical and environmental factors. The sudden change of wind direction and wind speed in the air layer below 600 meters is called low-altitude wind shear, which is recognized by the aviation industry as the "killer" of aircraft during take-off and landing stages. Low-altitude wind shear has the characteristics of sudden occurrence, short time, small scale, and high intensity. In order to ensure flight safety, the best way to deal with low-altitude wind shear is to avoid it. ...

AI Technical Summary

Problems solved by technology

Low-altitude wind shear has the characteristics of sudden occurrence, short time, small scale, and high intensity. In order to ensure flight safety, the best way to deal with low-altitude wind shear is to avoid it. To avoid wind shear, you must first be able to detect or Predict the time and place where it will appear, but it is difficult for conventional weather radars to complete this task. From the current relevant literature, we can see a series of studies on airborne forward-looking windshear radars that can detect and warn of windshear, so as to ensure that aircraft Safety during takeoff and landing

[0003] Algorithms proposed so far for the estimation of echo wind speed in low-altitude wind shear wind field mainly include Fast Fourier Transform (FFT) and Pulse Pair Processing (PPP). Both of these methods need to filter the ground clutter first, and then estimate the wind speed, which may cause the pole to drift in the direction of the ground clutter, so that the estimation of the wind field echo is not accurate enough to reflect the real wind speed well.

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