Blind estimation of directional properties of room reverberation using a spherical microphone array

This paper presents an experimental study on a novel technique to blindly estimate the directional properties of room reflections using a spherical microphone array. The algorithm is developed based on a spatial correlation model formulated in the spherical harmonics domain. This model expresses the cross correlation matrix of the recorded soundfield coefficients in terms of direct sound and reflections. The directional gain of the reflected path is estimated from the above model, which provides information on the DOAs of dominant wall reflections. The practical feasibility of the proposed algorithm is evaluated using a subset of the speech corpus from the ACE (Acoustic Characterization of Environments) Challenge.