On acoustic source localization in a reverberant environment based on image method

Abstract

The paper presents the acoustic source localization in a 2D rectangular room by using the measured acoustic impulse response. Two cases are considered: a corner of a room and a corridor. In each case, a theoretical analysis based on image source model is presented. To identify the source position, until some ambiguities, a single acoustic impulse response is required. To overcome these ambiguities, two additional impulse responses are needed. The three impulse responses can be obtained in the same time or by sequential measurements, two at a time. Experimental results obtained by real measurements which prove the theoretical ideas are presented. Acoustic source localization and room geometry estimation are two topics in very strong connection. Their purpose is to determine the coordinates of an acoustic source in a rectangular room and also to determine the dimensions of the room. In order to obtain these results, the acoustic impulse response from the source to a microphone in that room must be determined. By analyzing the impulse response, the peaks which correspond to the reflections from the room walls are extracted and then the source coordinates and room dimensions can be computed. Some papers [1], [3], use only one microphone (a single acoustic impulse response), other use an array of microphones (multiple responses) [2]. The presented paper parallels the ideas of a very recent published paper [1]. However, that paper considers that a measured impulse response is available and the correspondence between the peaks of the impulse and the reflections is al-ready done. However this is not a simple task as we have demonstrated in the paper. In the corner case we used the expression (1) to compute the distance source-microphone, where ∆τi,0 are called times difference of arrival (TDOA). 22 2 1,0 2,0 3,0 0 3,0 1,0 2,0