An analysis of the effect of larynx-synchronous averaging on dereverberation of voiced speech

The SMERSH algorithm is a physiologically-motivated approach to low-complexity speech dereverberation. It employs multichannel linear prediction to obtain a reverberant residual signal and subsequent larynx-synchronous temporal averaging to attenuate the reverberation during voiced speech. Experimental results suggest the method is successful but, to date, no detailed analysis of the theoretical basis of the larynx-synchronous averaging has been undertaken. In this paper the SMERSH algorithmis reviewed before focussing on the theoretical basis of its approach. We showthat the amount of dereverberation that can be achieved depends on the coherence of reverberation between frames. Simulations show that the extent of dereverberation increases with reverberation time and give an insight into the tradeoff between dereverberation and speech distortion.