MVDR based feature extraction for robust speech recognition

Abstract

This paper describes a robust feature extraction method for continuous speech recognition. Central to the method is the Minimum Variance Distortionless Response (MVDR) method of spectrum estimation and a feature trajectory smoothing technique for reducing the variance in the feature vectors. The above method, when evaluated on continuous speech recognition tasks in a stationary and moving car, gave an average relative improvement in WER of greater than 30%.