Noise suppression method for body-conducted soft speech enhancement based on external noise monitoring

摘要

This paper presents a novel approach to suppressing adverse effects of external noise on body-conducted soft speech for silent speech communication in noisy environments. Nonaudible murmur (NAM) microphone as one of the body-conductive microphones is capable of detecting very soft speech. However, body-conducted soft speech easily suffers from external noise owing to its faint volume. To address this issue, the proposed method additionally uses an air-conductive microphone to detect only an external noise signal and uses the detected external noise signal to suppress its effect on the body-conducted soft speech. A semi-blind source separation technique is app??ed to the proposed method for estimating a linear filter to suppress the noise components without voice activity detection. Experimental results demonstrate that the proposed method yields 10 dB SNR improvements in 80 dBA noisy conditions and also yields significant improvements in sound quality of body-conducted soft speech.