APPARATUS FOR AUTOMATIC SPEECH RECOGNITION

An apparatus and method for recognition of sentences comprised of utterances separated by short pauses, the utterances representative of both isolated words and connected words. Speech to be recognized is converted into frames of digital signals. Selected ones of the frames of digital signals are compared with isolated word and connected word templates stored in a template memory. Recognition of isolated words is done by comparing the selected frames of digital signals with the isolated word templates in accordance with a windowed dynamic programming algorithm having path boundary control, while connected word recognition is accomplished by comparing selected frames of digital signals with the connected word templates in accordance with a full DPA having path score normalization and utterance frame penalty calculation capability. Variable frame rate encoding is used to identify the selected frames of digital signals. Syntax control includes selecting the isolated word and connected word templates to be compared after each utterance and includes combining the recognized isolated words and connected words into sentences in accordance with the predefined syntax after the end of the sentence has been detected. A logical set of connected words are the connected digits.