In set-top videoconferencing, the complete videoconferencing system ts unobtrusively on top of the television. The microphone sound pickup system is one of the most important functional blocks with constraints of small size, high performance, and low cost. Persons speaking several feet away from the system must be picked up satisfactorily while noise generated internally in the system by the co...

One of the key technologies for natural man-machine interface is hands-free speech recognition. The per­ formance of hands-free distant-talking speech recog­ nition will be seriously degraded by noise and rever­ beration in real environments. A microphone array is applied to solve the problem. When applying a micro­ phone array to speech recognition， parameters such 出 number of microphone eleme...

While close talking microphones give the best signal quality and produce the highest accuracy from current Automatic Speech Recognition (ASR) systems, the speech signal enhanced by microphone array has been shown to be an effective alternative in a noisy environment. The use of microphone arrays in contrast to close talking microphones alleviates the feeling of discomfort and distraction to the...

This study looks at two ways of extracting a glottal waveform from recorded speech. One way is to inverse filter the flow at the mouth. Another is to inverse filter the microphone signal. Theoretically, the microphone signal is considered to be the equivalent of a first order differentiation of the flow signal recorded at the lips. Recording the oral airflow is more complicated than the recordi...