Broadband DOA estimation using "spatial-only" modeling of array data

Most of the existing techniques for DOA estimation of broadband sources use both spatial and temporal modeling. This may lead to increased complexity besides a large algorithmic delay. In this paper, we propose a technique th at employs only spatial information in the form of a single spatial array c ovariance matrix, Assuming, the source to have an ideal bandpass power spec tral density, we formulate two subspace-based search functions for the esti mation of DOA's of broadband sources. One of these employs a multidimension al search in the parameter space, whereas the other requires a MUSIC like o ne-dimensional (1-D) search. The multidimensional cost function is shown to be consistent, yields performance close to the CR bound, and is insensitiv e to correlation between sources. Both the proposed methods are shown to be robust to deviations from the assumption of ideal bandpass power spectral density used in their formulation.