Moving Sound Source Tracking in Wide Space by Multiple Microphone Arrays

This paper describes about a method for tracking a moving sound source based on multiple microphone arrays. A moving sound source tracking over a few meters, e.g. over ten meters, is investigated. A key idea of tracking is using multiple microphone arrays. When a sound source moving over five meters is tracked by a single microphone array, a sound source localization accuracy decreases as a distance between a microphone array and a sound source increases. To solve this problem, we propose to distribute multiple microphone arrays at intervals of several meters and selectively use two microphone arrays. A proposed method localizes a moving sound by using microphone arrays, of which positions are the closest and the second closest to the sound source. As a sound source moves and changes position, we have to re-select two microphone arrays. We also develop an automatic switching method. We evaluate tracking accuracy of a proposed method in a simulation and in a real environment. A sound source tracking experiment using three microphone arrays of which spatial intervals are four meters is conducted in a real environment. It is demonstrated that a proposed method shows high accuracy.