LSI implementation of a pattern matching algorithm for speech recognition

Many speech recognition systems contain the foUowing functional blocks: a voice input circuit, a feature extractor (analyzer), a unit for calculating the distance between input and standard patterns at every frame, a memory for storing standard patterns, a unit for matching whole word patterns (a pattern matching circuit), and a final decision and system control circuit. The pattern matching circuit is independent of the recognition algorithm and requires many conventional integrated circuits for implementation. Therefore, we decided to develop a custom integrated circuit for the pattern matching function. Due to its original architecture, our integrated circuit is able to execute in real time a continuous nonlinear matching process and is able to handle large volumes of data. This integrated circuit has been designed to be suitable for both isolated word recognition and connected speech recognition. The circuit has been tested in a pilot isolated-word and connected-speech recognition system. In this paper, the authors describe this integrated circuit´s specifications, architecture, and performance, as well as its application in the model system.