Study On Wind Turbine Echo Recognition And Suppression Method Of Airborne Multi-channel Radar

With the popularization of wind energy,the large-scale construction of wind farms will make the airborne radar detect the wind turbine.Most of the wind turbines consisting of large-sized metal materials will lead to strong radar echo amplitude of the wind turbine.And the rotation of the wind turbine blade will also cause Doppler frequency to widen,causing severe interference for the detection of airborne radar motion targets.This article conducts research on the above problems.The main work content of this article includes:Wind Turbine Echo Modeling and Simulation.First of all,under the distant field plane hypothesis,based on the limited meta-division idea and considering the effect of radar resolution,build a single-channel radar wind turbine echo model.And analyze the frequency domain characteristics and time-frequency domain characteristics of the wind turbine echo.The experimental results show that the frequency domain characteristics of the wind turbine echo model in this article are closer to the results of the measured data.Then,build a multi-channel radar wind turbine echo model,and analyze its space time characteristics.Results show that wind turbine doppler frequency has a width of the frequency,due to the rotation of the blades,and it will present a straight line characteristics in the space time spectrum.Finally,the multi-diameter effect will be caused by the wind turbine mast,so the multi-diameter signal model of the wind turbine echo is constructed and the simulation analysis is performed.Results indicate that the wind turbine’s blade multi-diameter signal has the same rotation cycle,and the maximum doppler frequency caused by the blades is different.Typical Wind Turbine Echo Suppression Method.Covering the target is covered by the wind turbine miscellaneous waves,the applicability of the four typical wind turbine hybrid suppression methods is analyzed.Under a short time observation conditions,the compensation method in the spectrum is only applicable to wind turbines and targets are located at different distances;multiframe detection methods are inhibiting the wind turbine and moving targets in the same distance unit,but it takes multiple observations.Under long-term observation conditions,the spectral relief method requires accurate estimation of the parameters of the outlet turbine,which is no longer applicable to the wind turbow;based on TRIAA and L-statistical methods is not applicable to the strong wave environment of the airborne radar.Two-step Clutter Suppression Algorithm Based on Wind Turbine Space-Time Spectrum and Orthogonal Projection.In short-term observation of airborne radar,the wind turbine echo will submit the target signal and cause the clutter covariance matrix estimate to be inaccurate,so that clutter suppression performance is lowered.Therefore,first uses the straight line characteristics of the wind turbine in the space-time spectrum,and selects the distance unit of the potential wind turbine from the training data to avoid the wind turbine pollution clutter correlation matrix.Then,for the distance unit of the wind turbine,the space frequency of the wind turbine and the width of doppler will be calculated by the space time spectrum of these units.By estimating the resulting parameters,it is intended to be orthogonal,and the echo data is projected to the matrix of the matrix to complete the inhibition of the wind turbine clutter.Finally,use the estimated resulting clutter covariance matrix to suppress the ground clutter.The simulation results show that the method can detect moving targets at the same distance unit in the airborne radar short observation time.