Research On DOA Estimation Of Sparse Arrays Based On Matrix Filling

Direction of arrival(DOA)estimation is one of the main research directions in array signal processing.It has been widely used in many important civil and military fields.Sparse array breaks through the limitation of half wavelength and the antenna array with larger aperture can be constructed under the same array number,which has higher freedom and direction finding accuracy.The purpose of this thesis is to study the DOA estimation of sparse array,explore the application of matrix completion theory to spatial spectrum estimation to improve the performance of DOA estimation of sparse array.The main work of this thesis is as follows:(1)Based on the study of the antenna array model and the array receiving signal model,analyzing two classical DOA estimation algorithms of Multiple Signal Classification(MUSIC)and Estimation Signal Parameter via Rotational Invariance Techniques(ESPRIT),and comparing the performance of the two algorithms in DOA estimation of array signal by taking the uniform linear array as an example.(2)Matrix completion theory is studied.Based on the analysis comparison of several common matrix completion algorithms: SVT,FPC and ALM algorithms,aiming at their shortcomings in error performance,based on ALM algorithm,the thesis proposes PD-ALM algorithm which effectively reduce relative error of the ALM algorithm completing matrix by introduction of punishment decomposition in the matrix rank minimization solution.(3)Aiming at poor performance in DOA estimation of one-dimensional sparse array,firstly,the thesis proposes sparse array DOA estimation method based on the snapshot matrix completion,by completing the snapshot matrix,which realizes a high-performance DOA estimation.Then,the thesis proposes sparse array DOA estimation method based on covariance matrix completion to reduce computation of the algorithm.(4)Aiming at the problem that there are many missing data in the covariance matrix of2 d sparse array received signals,firstly,the thesis proposes the covariance matrix reconstruction algorithm based on data average,which effectively improves the performance of DOA estimation.Because the covariance matrix reconstruction algorithm based on data average only apply to the incoherent signals source,the thesis proposes the covariance matrix reconstruction algorithm based on the first row data,which avoids the interference between the signals,effectively improves the performance of DOA estimation under coherent signals source.