Low level wind shear velocity estimation method based on compressed sensing

Abstract

A low level wind shear velocity estimation method based on compressed sensing comprises the following steps: 1), utilizing Doppler vectors to establish a redundant dictionary so as to achieve sparse representation of an echo signal; 2), establishing a measurement matrix; 3), computing a measured value after the signal is compressed; 4), utilizing a regularization orthogonal matching pursuit algorithm to reconfigure a sparse signal; 5), utilizing a non-zero value in a complex amplitude estimation value to obtain Doppler frequency estimation of the radar echo signal; 6), computing a position of a maximum value in the complex amplitude estimation value after clutter rejection is performed, namely a velocity estimation result of a wind shear signal; and 7), repeating the step 3) to the step 6), judging whether the velocity estimation is accomplished according to the number of range units, and sequentially performing velocity estimation on echo data of all the range units within the scope. Aiming at the problem that velocity estimation precision is poor when the number of pulses is small and a signal to noise ratio (SNR) is low, the low level wind shear velocity estimation method based on the compressed sensing is provided. The low level wind shear velocity estimation method based on the compressed sensing can enable frequency spectrum resolution to be greatly improved while the accurate velocity estimation can be obtained, namely, the wind shear signal and the ground clutter signal can be well distinguished, wherein an interval between a frequency domain of the wind shear signal and a frequency domain of the ground clutter signal is very close.

Description

technical field [0001] The invention belongs to the technical field of airborne meteorological radar low-altitude wind shear detection, in particular to a method for estimating low-altitude wind shear wind speed based on compressed sensing. Background technique [0002] As one of the weather phenomena that poses the greatest threat to air transport safety, low-altitude wind shear mainly refers to the weather in which the wind direction or speed changes rapidly within a short distance at the same or different heights (about 600m) during the aircraft take-off and landing phase. Phenomenon. Low-altitude wind shear occurs suddenly and has the characteristics of short duration, high impact intensity, and high risk. Due to the limited controllable height space during the take-off and landing phase of the aircraft, if the wind shear is strong, it will easily cause a serious crash. Therefore, the research on low-altitude windshear detection technology has become an important topic...

AI Technical Summary

Problems solved by technology

When the number of pulses is small and the signal-to-noise ratio is low, existing wind speed estimation methods such as FFT method and PPP method have technical problems such as limited spectral resolution and reduced estimation performance.

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