DOA Estimation Based On Beamspace Super-resolution

Direction of arrival(DOA)estimation is an important research direction of array signal processing,which is widely used in radar,sonar,wireless communication and other fields.Due to the good performance of beam space processing in reducing complexity and improving performance,it has attracted extensive attention in the past few decades.Various classical DOA estimation methods have been applied to beamspace.Inspired by the concept of compressed sensing,some discrete sparse representation methods are extended to beamspace to improve the performance of DOA estimation in the case of low signal-to-noise ratio and lack of snapshot.However,the discrete sparse restoration method will face the problem of base mismatch when meshing.In order to solve this problem,a super-resolution method for gridless compressed sensing,called atomic norm minimization(ANM),has been proposed recently.By using the Toeplitz structure of covariance matrix,ANM method is applied to DOA estimation of linear array and rectangular array.In this paper,combining beamspace processing with super-resolution methods such as atomic norm minimization,the beamspace DOA estimation method based on uniform linear array and area array is studied,and its application in channel estimation is discussed.The main research contents are as follows:1.A low complexity one-dimensional linear array DOA method based on beam space super-resolution is studied.Aiming at the one-dimensional uniform linear array for DFT beam dimensionality reduction,a low complexity beamspace super-resolution DOA estimation method is studied based on beam space atomic norm(BS-ANM)optimization.A low complexity solution method based on semidefinite programming(SDP)and alternating direction method of multipliers(ADMM)is presented,and the one-dimensional linear array beam space super resolution DOA estimation based on beamspace atomic norm minimization is realized.The complexity analysis and simulation results show that compared with the traditional atomic norm DOA estimation algorithm,this method reduces the amount of calculation and has better direction finding performance.2.In order to obtain the elevation and azimuth of the incident signal at the same time,a two-dimensional array DOA estimation algorithm based on beamspace super-resolution is studied in this paper.Firstly,for the two-dimensional beamspace output signal,a SDP solution method based on atomic norm minimization is studied,the corresponding ADMM algorithm is given,and the DOA is estimated by 2D-ESPRIT algorithm.On this basis,a DOA estimation method of beam space two-dimensional array based on Wasserstein distance is studied,and a fast solution algorithm based on ADMM is given.The effectiveness of this method is verified by simulation.3.The BS-ANM algorithm introduced in research content 1 is applied to the uniform linear array with DFT beamspace,and its application in channel estimation is studied.Simulation results show that compared with the existing methods,the proposed method has good channel estimation performance.