Intelligibility enhancement of bone conducted speech by an analysis-synthesis method

This paper proposes an intelligibility enhancement technique for bone conducted (BC) speech without exploiting any spectral characteristics of normal air conducted (AC) speech. Due to its robustness against ambient noise, BC speech has recently received a lot of attention. Particularly, it has proven to be very suitable for military, rescue and security operations. However, BC speech suffers from lower intelligibility for it lacks higher frequency components. This appears as a tradeoff for human-machine communication like speech recognition and understanding. The proposed technique enhances the weak higher frequency components by an analysis-synthesis method based on linear prediction. Preliminary listening test and spectrograms produced from the synthesized BC speech demonstrates significant intelligibility enhancement when compared with the original BC speech.