Research On DOA Algorithm Based On Uniform Circular Array

Array signal processing is an important branch of the signal processing and it hasbeen widely used in wireless communication, radar, sonar and other fields. An importanttask in the process of researching on array signal processing, is to determine the directionof arrival (DOA) of the spatial signal. The direction of arrival (DOA) estimation plays avery important role in the comprehensive reconnaissance of targets, precise positioningand monitoring. Therefore, in the study of spatial spectrum estimation, the algorithm ofthe direction of arrival (DOA) estimation is of considerable realistic significance.Because the direction-finding of the uniform circular array is based on DOAestimation of the uniform linear array (ULA), this thesis first researches the algorithm ofDOA estimation of the uniform linear array (ULA) before exploring the algorithm ofuniform circular array’s DOA estimation. Then, the thesis analyzes several classicalalgorithms of the direction-finding of the uniform linear array, which is in the models ofnarrowband signal, and the MUSIC algorithm and Root-MUSIC algorithm are mainlystudied. After analyzing the features of the mathematical model of the uniform circulararray, on the basis of Root-MUSIC algorithm, two improved algorithms that concern aboutthe direction-finding of the uniform circular array have been proposed. To reduce thecomputation and meet the actual needs of the project, this thesis put forwards an improvedRoot-MUSIC algorithm for real valued beam space, which will realize the purpose ofreducing computation. Considering the great number of array elements in reality and thelarge occupied space, this thesis has proposed an improved Root-MUSIC algorithm of asparse matrix. This algorithm will deal with the noise sub-space algorithm through thesparse matrix, and, on the premise that the estimation accuracy and the resolution could beguaranteed, decrease the number of array elements to save cost. The result of theMATLAB programming simulation of these two improved algorithms has proved theeffectiveness of the improved algorithms.