Incorporating Information From Syllable-Length Time Scales Into Automatic Speech Recognition

Including information distributed over intervals of syllabic duration (100--250 ms) may greatly improve the performance of automatic speech recognition (ASR) systems. ASR systems primarily use representations and recognition units covering phonetic durations (40--100 ms). Humans certainly use information at phonetic time scales, but results from psychoacoustics and psycholinguistics highlight the crucial role of the syllable, and syllable-length intervals, in speech perception. We compare the performance of three ASR systems: a baseline system that uses phone-scale representations and units, an experimental system that uses a syllableoriented front-end representation and syllabic units for recognition, and a third system that combines the phone-scale and syllable-scale recognizers by merging and rescoring N-best lists. Using the combined recognition system, we observed an improvement in word error rate for telephone-bandwidth, continuousnumbers from 6.8% to 5.5% on a clean test set, an..