Reverberant sound field analysis using a microphone array

The use of microphone arrays for sound pickup in reverberant environments has been proposed by many authors. The observation on the M microphones can be decomposed into a spatially coherent and an incoherent part. The first one is due to perfect (plane or spherical) sound waves caused by the direct path and specular reflections, whereas the latter is caused by diffusion, diffraction, non-perfect reflections, electrical and quantization noise. In this paper we firstly present a deflation method to detect and localize spatially coherent waves from the measured impulse responses. In a second step the filters which model the source directivity and the reflecting materials are estimated. The model takes into account nearfield delay, range attenuation, microphone and source directivity as well as non-trivial reflections.