An acoustic Doppler-based front end for hands free spoken user interfaces

Two major problems facing hands-free spoken user interfaces are first, to be able to identify accurately when it is addressed and second to effectively determine the start and end points of utterances so that proper sections of speech can be used for further processing and recognition tasks. Accurate determination of end points not only aids accurate noise estimation but also improves speech recognition accuracy. This paper presents an acoustic Doppler sensor based front end for a hands-free spoken user device which provides an efficient and effective solution to both the aforementioned problems.