Enhancement of Bone Conducted Speech Signal by Wavelet Transform

摘要

To acquire the speech generated by the user, communication devices make use of an air microphone which, by far, is the most common and simple signal acquisition method. This leads to the gathering of background noise along with the actual speech signal and makes the whole communication link noisy. To prevent this, proposal of using bone conducted signal is made. As bone prevents passing of vibration signals which are of frequencies greater than 1.5kHz, transmitted signal will remain inherently free of ambient noise. However, bone conducted signals are usually inferior in intelligibility and SNR as compared to the microphone signals, hence, two signal processing approaches, using MFCC and wavelet transform, are proposed which can improve such parameters with an attempt to increase the quality of communication link between transmitter and receiver.