The Broadband Signal DOA Estimation Algorithm Based On Uniform Linear Array

Spatial spectrum estimation is an important research direction in array signal processing,which focuses on the location and direction finding of the signal source by spatial sensor array.The direction of arrival(DOA)estimation is the most important part of spatial spectrum estimation,which plays a very important role in the all-orientation search and precise location of the target source.Therefore,DOA estimation technology has a very important practical significance in the field of space direction finding and signal location.The DOA estimation technique of broadband signal is mainly based on DOA estimation of narrowband signal,therefore,this paper firstly researches the Classical MUSIC algorithm of narrowband.Aiming at the shortcoming that the MUSIC algorithm which can not be related to the demodulation of coherent sources,a modified MUSIC algorithm for coherent sources is proposed.At the same time,this new algorithm is applied to the improvement of broadband ISM algorithm.Under the premise of ensuring the estimation accuracy and resolution,both of the classical MUSIC algorithm and ISM algorithm can realize the direction finding of coherent signals,which broaden the scope of the application of these two algorithms.In DOA estimation of broadband signals,a CSM algorithm based on spatial smoothing difference is proposed,whose foundation is the classical CSM algorithm.This algorithm not only takes advantage of the information of each subarray but also makes full use of the correlation between the subarrays to reduce the influence of array errors on the DOA estimation,improving the accuracy of the algorithm,so that the improved algorithm can achieve the unbiased estimation for the signals.The above algorithms are simulated by MATLAB,and verifies the feasibility of the improved algorithm.