Sound field diffusivity estimation using spherical microphone arrays

Abstract

During the last decade, spherical microphone arrays have become increasingly popular in the acoustic community. These microphone arrays can be used for various applications such as beamforming, sound field reproduction and spatial sound field analysis. Within the context of sound field analysis and room acoustics, estimating the diffusivity of the sound field at a particular time instant is useful. In this paper we present an algorithm for evaluating the diffusivity of sound fields recorded by spherical microphone arrays. Results of numerical simulations show that this algorithm is more robust to the presence of sound sources in opposite directions to each other, as compared to previously proposed methods. In addition the algorithm provides an upper bound for the number of dominant sound sources.