Speech enhancement using the multistage Wiener filter

In this paper we develop a subspace speech enhancement approach for estimating a signal which has been degraded by additive uncorrelated noise. This problem has numerous applications such as in hearing aids and automatic speech recognition in noisy environments. The proposed approach utilizes the multistage Wiener filter (MWF). This filter is constructed from a Krylov subspace associated with the Wiener filter for this problem. The principles and performance of this approach are described. The approach provides signals with higher quality compared to the full Wiener filter and the signal subspace method as evident from informal subjective listening tests, the commonly used PESQ objective test and improved speech recognition performance. In informal listening tests the listeners preferred the MWF enhancement over the other enhancement methods.