Fast wideband source separation based on higher-order statistics

In this paper we develop an algorithm to improve the accuracy of the estimation of the direction of arrival of the wide-band sources. It is well known that when the noise cross-spectral matrix is unknown, these estimates may be grossly inaccurate. Using both the fourth order cumulant for suppression of the Gaussian noise, the transformation matrices for estimating the coherent signal subspace and a noneigenvector algorithm a robust method for the source characterisation problem in the presence of noise with an unknown cross-spectral matrix is developed. We show that the performance of bearing estimation algorithms improves substantially when our robust algorithm is used. Simulation results are presented for the unknown noise spectral matrix.