Use of reflected wavefronts for acoustic source localization with a line array

This paper addresses the problem of acoustic source localization with a line microphone array. Although the device has a one-dimensional geometry, in presence of reflected wavefronts within an enclosure it is possible to obtain good localization performance (even in terms of 3D coordinates) if the information provided by mutual delays between the arrivals of direct and reflected waves is exploited. Acoustic maps of a room with known reflecting surfaces are produced by matching the phase information measured by means of the array with a sound propagation model based on the image method. The here proposed method, MultiPath Global Coherence Field (MP-GCF), can be interpreted as a generalization of GCF. With MP-GCF the assumption that direct wavefronts dominate over reflections is not required anymore. Experiments performed with real data acquired in a reverberant room show that, using a line array, the proposed method largely outperforms the results obtained with GCF. Simulations were also carried out to investigate how performance changes under different environmental conditions.