A High-Speed HMM VLSI Module with Block Parallel Processing

This paper considers the continuous distribution HMM and discusses speed improvement by parallel processing and VLSI design, aiming at the realization of a high-speed speech recognition LSI. The continuous distribution HMM has high recognition performance. But a large amount of computation is required for the calculation of the output probability, and speed improvement is highly desirable. Regarding speed improvement of the output probability calculation, this paper proposes blockwise parallel processing and an architecture for performance. The minimum optimal bit width is investigated for recognition by fixed-point operations. Based on the proposed architecture, VLSI design for an HMM is performed and the result is evaluated. It is shown that the proposed architecture has sufficient power to construct a recognition system that can respond in real time, requiring 3 ms for the recognition processing of 100 words. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(5): 12–23, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10099