Speech signal captured by PVDF sensor

The spoken communication between human and a machine is difficult and challenging task. Under the noisy background, it is more difficult as the speech collecting microphone collects noisy signal. In this paper we describe a PVDF based microphone that collects bone conducted sound of the speaker while discriminating the background noise. The PVDF microphone is placed on the forehead of the speaker. Since the proposed microphone collects bone conducted sound, it contains high frequency components in feeble or little amount as the human bone acts like a low pass filter with upper cut off frequency ranging from 1 kHz to 1.5 kHz.