Narrowband voice system.

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Author
Hitchcock, Raymond Roy
Date
1979-06Advisor
Ewing, Gerald D.
Metadata
Show full item recordAbstract
The problem of how to accommodate more simultaneous users
in a given bandwidth communications channel was examined. It
was determined that voice signals could be reduced in bandwidth
by 50 percent. Two speech formants, Fl and F3 , were
filtered from the speech signal and frequency translation
performed to form a compact audio signal. At the receiver this
process is reversed and the formants returned to their normal
spectral positions. Intelligibility scores of 94 percent were
obtained in a listening test conducted using the two formants
Fl (250-650 Hz) and F3 (1950-2450 Hz).