A Low Complexity Robust Parameter Estimator for Distributed Source

A new ESPRIT-like algorithm is proposed for the estimation of the central direction of arrival (DOA) of a single distributed source. It is showed that the two signal subspaces are related by a rotation matrix, which can be used to estimate the central DOA. The so-obtained DOA estimate does not depend on any assumption on the spatial distribution of the source and is hence robust to mismodeling. For coherently distributed source, the angular spread is estimated by constructing a one-dimensional (1-D) Capon beamforming spectrum. The parameter angular spread is included in the constraint, so the algorithm can be applied in large angular spread scenarios. Additionally, instead of a two-dimensional (2-D) search, the proposed algorithm requires only one step 1-D search for estimating the angular spread. Numerical examples illustrate the proposed method is not only effective, but also enjoys better performance