A noise-robust speech input interface for information kiosk terminals

In social amenity apparatus such as information terminals or oil-line shopping terminals and ticket vending machines, more natural and smoother communication between machines and humans is made possible by incorporating speech recognition, thus rapidly enhancing operation and convenience. In this paper, we will describe the trial production of an information kiosk terminal equipped with speech recognition and the noise reduction technique adopted as a speech input interface. In general, the aforementioned system equipment is installed in public spaces such as stations. Therefore, robust speech recognition performance is required even in the worst noise environments. For the realization of this antinoise capability, we have used noise reduction based on both a microphone array and spectral subtraction (SS). Experiments with evaluation data recorded in real environments indicate that a recognition performance of over 90% in isolated-word recognition of 216 words uttered by all unspecified speaker is achieved by the combined use of a 32-channel microphone array and SS. (C) 2004 Wiley Periodicals, Inc.