Accession Number : ADA180796
Title : Topics in Speech.
Descriptive Note : Technical rept.,
Corporate Author : MITRE CORP MCLEAN VA JASON PROGRAM OFFICE
Personal Author(s) : Despain,A. ; MacDonald,G. ; Press,W. ; Rothaus,O.
Report Date : MAY 1987
Pagination or Media Count : 61
Abstract : This report continues the initial JASON work in speech. Bispectrum and the nonlinear sensing mechanism of the human ear are this effect's principal topics. The Wigner distribution is supported as the best current method of representation of the bispectrum and its essential character of intrasignal phase coherency/description. Several presentation means for this distribution are discussed, and further work is recommended and promised. The ear is described in some detail, with its nonlinear character being modeled as a regenerative receiver. The observed acoustic signal generation by the ear is accounted for by such a model. A regenerative feedback model and the limited bispectral observation of audio spectrograms strongly suggest that the bispectrum of the voice carries essential information and the message and the source. It is speculated that an accurate appreciation for cochlear mechanics can bring us much closer to understanding speech discrimination by allowing researchers to focus on the signal as processed in the demonstrably excellent human processor.
Descriptors : *ACOUSTIC SIGNALS, *SIGNAL GENERATION, *EAR, *STATISTICAL ANALYSIS, COCHLEA, DETECTION, DISCRIMINATION, FEEDBACK, HUMANS, MECHANICS, MODELS, NONLINEAR SYSTEMS, PROCESSING EQUIPMENT, RECEIVERS, REGENERATION(ELECTRONICS), SPEECH, SOUND
Subject Categories : Acoustics
Statistics and Probability
Anatomy and Physiology
Distribution Statement : APPROVED FOR PUBLIC RELEASE