Wind profile radar clutter suppression method based on fraction order Fourier transform

Abstract

The invention relates to a clutter suppression method, in particular to a wind profile radar clutter suppression method based on the fractional Fourier transform, which belongs to the technical field of signal processing and detection. The method of the invention comprises the following steps: firstly, the optimal fractional order Alpha opt is selected; secondly, time-domain data after the coherent accumulation is carried out with the fractional Fourier transform under the optimal fractional order Alpha opt to obtain the corresponding fractional order-domain signal form; the clutter interference detection threshold is then determined according to the statistical characteristics of all the order moments of the received signal in the fractional order-domain; the data after the suppression is finally carried out with the inverse fractional Fourier transform to obtain the time-domain wind profile radar data after the removal of the clutter and complete the clutter suppression treatment based on the fractional Fourier transform. The wind profile radar received signal processed by the method can significantly improve the signal-to-noise ratio through the actual measurements.

Description

technical field [0001] The invention relates to a clutter suppression method, which is a method for suppressing clutter interference by a wind profile radar in the fractional Fourier domain, and belongs to the technical field of signal processing and detection. Background technique [0002] Wind profiler radar is an all-weather Doppler remote sensing device that continuously observes the distribution of atmospheric wind direction and speed with height. It achieves the purpose of wind measurement by detecting the weak signal reflected by atmospheric turbulence. The research on this technology began in the United States in the early 1980s. Due to its high real-time and high accuracy of wind measurement, it is one of the key technologies for small and medium-scale atmospheric detection. Wind profiler radar is widely used in meteorology, environmental protection, military and other fields. It has broad application and research prospects. The echo signal power of the wind profil...

AI Technical Summary

Problems solved by technology

The echo signal power of the wind profiler radar is weak (even less than -140dBm), while the amplitude of ground clutter and intermittent clutter is several orders of magnitude higher than the wind signal, which causes the effective data rate of the wind profiler radar to be low The main reason is to limit its application in airports, environmental protection and other fields. How to effectively suppress clutter and minimize the loss of useful signals is one of the problems to be solved in wind profiler radar signal processing.

At present, wind profiler radar mainly adopts classical signal processing techniques, such as pulse compression coding, DC removal, spectrum accumulation, spectrum cancellation, etc. Although it has a certain suppression effect on active interference, the signal-to-interference ratio has little improvement and the effect is not obvious

Images