In the system, a speech input uttered by a human is received by a microphone which outputs microphone output signals. The speech input received by the microphone is then recognized by a speech recognition unit, and a synthetic speech response appropriate for the speech input recognized by the speech...http://www.google.ca/patents/US5548681?utm_source=gb-gplus-sharePatent US5548681 - Speech dialogue system for realizing improved communication between user and system
