Beam-space processing with spatially interpolated wideband bearnformers for wideband direction-of-arrival estimation

In this paper, we present a method for widehaud direction-of-arrival (DOA) estimation, based on beam-space processing with spatially interpolated wideband heamformers (SIWB??s). The SIWB??s are designed to have frequency-invariant beam-response within a wide signal bandwidth. For wideband DOA estimation, these SIWB??s are used as spatial pre-processors transforming the widehand signals at the outputs of antenna array (element-space) into the heam-space signals prior to applying narrowband DOA estimation. The new SIWB-based method enhances the resolution of spectral estimation and reducing rootmean- square error of DOA estimation without increasing number of array elements. Furthermore, the proposed method is applicable for coherent sources without preliminary DOA estimates. The performance of the proposed method in comparison with the conventional methods is illustrated in simulation results. A preliminary analytical study of performance is also included.