Estimating direct-to-reverberant energy ratio based on spatial correlation model segregating direct sound and reverberation

A new approach for estimating the direct-to-reverberant energy ratio (DRR) using a microphone array is proposed. The method is based on a model of a spatial correlation matrix that segregates direct sound and reverberation. It estimates DRR from the power spectra of both components, which are derived from the correlation matrix of the observed signal. In experiments performed in simulated and actual reverberant environments, the proposed method mostly succeeded in estimating DRR accurately. We also present speech enhancement using binary masking as an example of an application of the estimated DRR. By utilization of the DRR as a factor to discriminate the distances of speakers, separation of speech signals whose sources were located in the same direction but at different distances was achieved.