Coherent signal classification using symmetry considerations

The problem of locating the directions of arrival of a set of coherent/correlated signals in an arbitrary noise field using multiple sensor elements is considered. It is shown that by making use of a symmetric array, it is possible to perform a preprocessing on the array output correlations to generate a set of new quantities that are functionally similar to the actual correlations in an incoherent environment. The orthogonality of the direction vectors corresponding to the true angles of arrival and a set of eigenvectors of the Toeplitz matrix generated from these new quantities is then made use of in estimating the actual multipath arrival angles.<>