An investigation of methods of improving the intelligibility of audio-frequency speech in noise
investigationofm00hudd.pdf (2.862Mb)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 retranslat ion 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 showings, that this processing results in a 20% improvement in speech intelligibility over audio clipping and filtering.
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This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.Collections
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