Robust MMSE filtering for single-microphone speech enhancement

Abstract

MMSE filtering of signals contaminated with additive noise is addressed with explicit uncertainty of the second-order target signal statistics. The unfortunate lack of stationarity of speech, and hence the phenomenon of musical noise in speech enhancement, is an ideal problem for the proposed approach. Specifically, we complement the established short-time power-spectral subtraction for speech power estimation with a prior of the momentary speech-power level. The MMSE estimator for Gaussian speech amplitudes is then derived under these circumstances. The potential for the enhancement of noisy speech is briefly demonstrated by SNR and PESQ analysis.