Localization Method of Spatial Wideband Sound Source on Distributed Circular Array

To enhance the resolution of sound source location, reduce computation cost and improve noise robustness, a localization method of spatial wideband sound source on distributed circular array is proposed. Firstly, the acoustic signal is converted into narrowband signal through focusing matrices. Then the product of spatial spectrum and the group delay function of its phase information could eliminate pseudo peaks and obtain high resolution DOA estimation in the group delay spectrum. Secondly, with the help of region centroid, the rough source region would be built on each projective planes of the spatial coordinate system. Then combine with the Search Region Contract (SRC) method realized region contract and gained the rough contract region. Finally, find the points corresponding to maximum cross power spectrum as the source localization estimation by using Steered Response Power with Phase Transform (SRP-PHAT) method in rough contract region. The method by using group delay function not only enhanced utilization rate of spatial spectrum information and the reliability of initial region but also gained the high resolution DOA estimation. The new method which combine SRC with SRP-PHAT can locking sound source position quickly and reduce searching complexity. In addition, the distributed array features with large aperture and not sensitive to position changes had greatly enhance noise robustness of the proposed system. Simulation results verify that the proposed method can realize a more precise source location estimation.