Multi-channel speech dereverberation based on a statistical model of late reverberation
Speech signals recorded with a distant microphone usually contain reverberation, which degrades the fidelity and intelligibility of speech, and the recognition performance of automatic speech recognition systems. A multi-channel speech dereverberation algorithm is presented which reduces spectral coloration and late reverberation. A spatially averaged amplitude spectrum is used to estimate the instantaneous amplitude spectrum of the clean speech signal, which is then further enhanced using an estimate of the power spectrum of the late reverberant signal. The power spectrum of the late reverberant signal is constructed from multiple microphone signals and a statistical model of late reverberation. The algorithm is tested using synthetic reverberated signals. The performances for different room impulse responses with reverberation times ranging from approximately 150 ms to 350 ms show significant reverberation reduction with little signal distortion.