Cover: The Role of Acoustic Processing in Speech Understanding Systems.

The Role of Acoustic Processing in Speech Understanding Systems.

Published 1973

by A. S. Hoffman

Purchase Print Copy

 Format Price
Add to Cart Paperback37 pages $20.00

Discusses methods and problems of acoustic signal processing for systems to enable machines to understand spoken communication. Emphasis is on research outside of the ARPA-sponsored SUR (Speech Understanding Research) study. This acoustic level processing includes three steps, not necessarily distinct: (1) preprocessing the original analog signal or its digitized form by basic techniques such as amplitude compression; (2) analysis of the preprocessed signals using fast Fourier transformations, digital filtering, etc.; and (3) parameterizing the results in phoneme-sized chunks by formats, autocorrelation techniques, etc. Problems include (1) environmental noise, (2) transducer limitations, (3) determining an appropriate parameterization technique, and (4) coping with wide phonetic, syntactic, and semantic variability of speech. Choice of the voice coding technique depends on the characteristics of the speech understanding system to be used. Many SUR workers are using linear predictive coding and formant tracking. Progress is being made in segmentation and in use of prosodic features. Uncooperative speakers remain a problem. 37 pp. Ref.

This report is part of the RAND report series. The report was a product of RAND from 1948 to 1993 that represented the principal publication documenting and transmitting RAND's major research findings and final research.

This document and trademark(s) contained herein are protected by law. This representation of RAND intellectual property is provided for noncommercial use only. Unauthorized posting of this publication online is prohibited; linking directly to this product page is encouraged. Permission is required from RAND to reproduce, or reuse in another form, any of its research documents for commercial purposes. For information on reprint and reuse permissions, please visit www.rand.org/pubs/permissions.

RAND is a nonprofit institution that helps improve policy and decisionmaking through research and analysis. RAND's publications do not necessarily reflect the opinions of its research clients and sponsors.