Microphone array speech dereverberation using coarse channel modeling

This paper presents a model-based method for the enhancement of multichannel speech acquired under reverberant conditions. A very coarse estimate of the channel responses associated with each source-microphone pair is derived directly from the received data on a short-term basis. These estimates are employed to modify the LPC residuals of the channel data in an effort to deemphasize the effects of reverberant energy in the resulting synthesized signal. The approach is robust to conditions of partial and approximate channel information. Specifically, the incorporated channel model requires only approximate times and amplitudes of the initial multipath reflections. In practice these impulses are responsible for the bulk of reverberant energy in the received speech signal and can be estimated to a sufficient degree on a time-varying basis