Research On DOA Estimation Algorithm For Automotive Millimeter Wave Radar Array With Non-ideal Factors

DOA(Direction of Arrival)estimation of signal is always an important measurement parameter for radar system target detection,target tracking and trajectory synthesis.DOA estimation algorithm has always been the hot direction of array signal processing.Angle measurement techniques based on different theories emerge in an endless stream,and most of them are based on ideal array model.However,in the actual engineering implementation process must consider the array non-ideal factors,the existence of these array errors makes the algorithm model mismatch,DOA estimation accuracy is reduced.For further engineering application,this paper studies the DOA estimation algorithm under non-ideal array factors,and analyzes the mutual coupling error and amplitudephase error of two important factors of array mismatch.This paper mainly explores from four aspects:In the first part,the DOA received signal model under non-ideal factors is established,and the influence of non-ideal factors on the performance of DOA algorithm is analyzed by taking uniform linear array as an example.The destruction of non-ideal factors on the performance of DOA estimation is studied based on two different theories of DOA estimation methods.Second part for automobile millimeter wave radar commonly used uniform linear array array structure,study its under the condition of mutual coupling error and amplitude-phase error correction algorithm performance.Several current mutual coupling error correction algorithms are introduced,and the DOA mutual coupling self-correction algorithm based on orthogonal matching pursuit is improved.The performance of the algorithm is compared with a simulation example.In this paper,three kinds of amplitudephase correction algorithms for uniform linear arrays are introduced,and the atomic norm minimization(ANM)self-correction algorithm is optimized for dimensionality reduction,which greatly reduces the operation time of ANM algorithm.The performance of the algorithm is verified by simulation.In the third part,the above correction algorithm is introduced to other array structures.The mutual coupling rank loss method and mode space transformation method are studied for uniform circular arrays,and their performance is verified by simulation.For uniform rectangular array,a fast 2-D DOA estimation algorithm was optimized to eliminate the effects of mutual coupling errors through three subarray models.The performance of the algorithm was compared with that of the existing algorithms.Simulation results show that the proposed algorithm can reduce the computational complexity under the premise of similar DOA estimation performance,and is more conducive to practical engineering implementation.The fourth part mainly verifies the measured data in the actual environment.Based on the existing radar platform,the processing flow of the measured data is analyzed comprehensively,and the performance of the available algorithm in this paper is measured.