Performance Analysis of Noisy Speech Recognition Depending on Parameters for Noise and Signal Power Estimation in MMSE-STSA Based Speech Enhancement

MMSE-STSA 기반의 음성개선 기법에서 잡음 및 신호 전력 추정에 사용되는 파라미터 값의 변화에 따른 잡음음성의 인식성능 분석

The MMSE-STSA based speech enhancement algorithm is widely used as a preprocessing for noise robust speech recognition. It weighs the gain of each spectral bin of the noisy speech using the estimate of noise and signal power spectrum. In this paper, we investigate the influence of parameters used to estimate the speech signal and noise power in MMSE-STSA upon the recognition performance of noisy speech. For experiments, we use the Aurora2 DB which contains noisy speech with subway, babble, car, and exhibition noises. The HTK-based continuous HMM system is constructed for recognition experiments. Experimental results are presented and discussed with our findings.