Separation of Cogerent Multi-path Signals with Improved MUSIC Algorithm

MUSIC algorithm is an effective method for direction of arrival(DOA), but it can only do with incoherent signals. There are coherent signal and related signal in the actual communication environment. If the condition does not meet, there will be bias occured and even failure in the use of MUSIC algorithm for signal DOA estimation. In order to solve the problem of the DOA estimation of coherent signals, an improved algorithm is presented in this paper. By processing the convariance matrix of the array output signal, the rank of the signal covariance is restored to Rank(Rx)= D, which can effectively estimate the signal DOA and identify the coherent signal source. Simulation results show that the DOA can be correctly estimationed when the signal interval is relatively small and the signal to noise ratio is small. This indicates that the algorithm is effective and has practical value in engineering.