Accession Number : AD0489799

Title :   AN INVESTIGATION OF METHODS OF IMPROVING THE INTELLIGIBILITY OF AUDIO-FREQUENCY SPEECH IN NOISE.

Descriptive Note : Master's thesis,

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s) : Huddy, Norman Walter, Jr

Report Date : OCT 1966

Pagination or Media Count : 62

Abstract : A discussion of the nature of speech is presented, followed by a review of speech processing to date, with emphasis on the characteristics of speech which must be retained for intelligibility. Methods of measuring speech intelligibility are described. The relative merits of abrupt and gradual audio clipping of speech are investigated, and two tone and articulation test results are presented showing that there is no significant difference in these methods of clipping with respect to speech intelligibility. Processing of speech to radio frequencies, filtering and retranslation to audio to improve the peak to average value ratio of the audio frequency prior to transmitting it through a noisy channel is investigated. Two tone and articulation test results are presented showing that this processing results in a 20% improvement in speech intelligibility over audio clipping and filtering. (Author)

Descriptors :   *AUDIO FREQUENCY), (*SPEECH, (*INTELLIGIBILITY, SPEECH), MEASUREMENT, PROCESSING, NOISE, CLIPPER CIRCUITS.

Subject Categories : Non-radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE