The Fusion of Distributed Microphone Arrays for Sound Localization

This paper presents a general method for the integration of distributed microphone arrays for localization of a sound source. The recently proposed sound localization technique, known as SRP-PHAT, is shown to be a special case of the more general microphone array integration mechanism presented here. The proposed technique utilizes spatial likelihood functions (SLFs) produced by each microphone array and integrates them using a weighted addition of the individual SLFs. This integration strategy accounts for the different levels of access that a microphone array has to different spatial positions, resulting in an intelligent integration strategy that weighs the results of reliable microphone arrays more significantly. Experimental results using 10 2-element microphone arrays show a reduction in the sound localization error from 0.9 m to 0.08 m at a signal-to-noise ratio of 0 dB. The proposed technique also has the advantage of being applicable to multimodal sensor networks.