Optimal quiescent vectors for wideband ML beamforming in reverberant fields

In this work, the behavior of the recently developed wideband maximum likelihood steered beamformer (ML-STBF) is analyzed under multipath conditions. In particular, the importance of an optimal choice of the quiescent vector to initialize the ML-STBF is pointed out. Some quiescent vectors, optimized on the basis of the previous analysis, are developed for the joint use with the ML-STBF and compared in simulation. It is shown that their use can significantly improve the output signal-to-noise ratio, the multipath suppression capability and the robustness with respect to focusing errors of the ML-STBF. © 2004 Elsevier B.V. All rights reserved.