Linguistic constraints in hidden Markov model based speech recognition

A speaker-independent, continuous-speech, large-vocabulary speech recognition system, DECIPHER, has been developed. It provides state-of-the-art performance on the DARPA standard speaker-independent resource management training and testing materials. The approach is to integrate speech and linguistic knowledge into the HMM (hidden Markov model) framework. Performance improvements arising from detailed phonological modeling and from the incorporation of cross-word coarticulatory constraints are described. It is concluded that speech and linguistic knowledge sources can be used to improve the performance of HMM-based speech recognition systems provided that care is taken to incorporate these knowledge sources appropriately