Simple computation of projection matrix for bearing estimations

In the paper the idea of computing a projection matrix for bearing estimations by using any M rows of the covariance matrix, where M is the number of sources, is extended to the cases of low signal/noise ratio (SNR) and totally correlated sources. For low SNR, the projection matrix can be obtained by using off-diagonal terms of M rows of the covariance matrix, and a reduced search vector can be used. For totally correlated sources, the idea of spatial averaging is adapted to compute the projection matrix. However, no averaging is actually carried out.