On a tradeoff between dereverberation and noise reduction using the MVDR beamformer

The minimum variance distortionless response (MVDR) beamformer can be used for both speech dereverberation and noise reduction. In this paper we analyse the tradeoff between the amount of speech dereverberation and noise reduction achieved by the MVDR beamformer. We show that the amount of noise reduction that is sacrificed when desiring both speech dereverberation and noise reduction depends on the direct-to-reverberation ratio of the acoustic transfer function between the desired source and a reference microphone. The performance evaluation supports the theoretical analysis and demonstrates the tradeoff between speech dereverberation and noise reduction.