A sparse reconstruction method for speech source localization using partial dictionaries over a spherical microphone array

Abstract

Sparse reconstruction methods have been used extensively for source localization over uniform linear arrays and circular arrays. In this paper a sparse reconstruction method for speech source localization using partial dictionaries over a spherical microphone array is proposed. The source localization method proposed in this work addresses two important research issues. It formulates the source localization problem in the spherical harmonics domain as a sparse reconstruction problem. Subsequently, a low complexity method to estimate the direction of arrival (DOA) of multiple sources is also proposed by using partial elevation angle dictionaries. The use of such dictionaries reduces the complexity of the search involved in the two dimensional DOA estimation. Source localization experiments are conducted at different SNRs and compared with conventional DOA estimation methods like MUSIC and MVDR. The experimental results obtained from the proposed method indicate a reasonable reduction in the localization error.