A new criterion for DOA estimation of coherent sources based on weighted spatial smoothing

In order to decorrelate the coherent sources perfectly, i.e. recover the smoothed source covariance matrix to a diagonal matrix, Wang et al. (2002) proposed a weighted spatial smoothing (WSS) preprocessing scheme. Based on the idea underlying WSS, a new criterion was proposed in this paper for the direction-of-arrival (DOA) estimation of coherent sources. Compared with the WSS the cost function constructed from the new criterion can achieve favorable DOA estimation of coherent sources without the prior knowledge of source direction and the de-noising preprocessing. In essence, the proposed criterion is no longer a preprocessing scheme since no following subspace-based algorithm are needed.