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Accession Number:
AD0753526
Title:
Helium Speech Unscramblers - A Critical Review of the State-of-the-Art.
Corporate Author:
FLORIDA UNIV GAINESVILLE COMMUNICATION SCIENCES LAB
Report Date:
1972-08-01
Abstract:
The development of saturation diving has enabled man to work in the sea at great depths and for long periods of time. This advance has resulted, in part, as a consequence of the substitution of helium for nitrogen in breathing gas mixtures. However, the utilization of HeO2 breathing mixtures at high ambient pressures has caused problems in speech communication in turn, electronic aids have been developed to improve diver communication. These helium speech unscramblers attempt to process variously the grossly unintelligible speech resulting from the effects of helium-oxygen breathing mixtures and ambient pressure, and to reconstruct such signals in order to provide adequate voice communication. The report presents a discussion of the effects of HeO2P on speech and then describes some of the techniques used to unscramble the distorted speech. Included among the techniques are frequency subtraction, tape recorder playback, vocoder approaches, digital coding and convolution processing. Author
Descriptive Note:
Technical rept.,
Supplementary Note:
See also report dated 1 Jul 72, AD-751 034.
Pages:
0034
Contract Number:
N00014-68-A-0173-0008
File Size:
0.00MB
