Accession Number : AD0776812

Title :   Optimal Digital Voice Transmission Vocoplexer.

Descriptive Note : Final rept. 29 Jun 71-22 Feb 73,

Corporate Author : BELL AEROSPACE CO BUFFALO N Y

Personal Author(s) : Hrinkevich,John

Report Date : FEB 1974

Pagination or Media Count : 83

Abstract : The Vocoplexer technique for reducing the transmission rate of a digitized multi-channel communications system was investigated. Statistical processing of PCM digitized voice to remove the idle time periods was analyzed and experimental hardware was designed and fabricated. The equipment built includes separate transmit and receive processors which function to compress the digitized output rate of a TD-353/U, 48-channel PCM multiplexer for transmission and then restore it to its original rate, following reception. Circuitry is included to interface with tropospheric scatter Radio Set AN/MCR-98 at its intermediate frequency of 70 MHz. Voice channel loading is provided through the use of 48 cassette tape players and an audio monitoring unit. The recorded voice tapes used are adjusted in content to provide an individual channel activity factor of 0.25. (Modified author abstract)

Descriptors :   *Vocoders, *Pulse communications, *Processing equipment, *Voice communications, Digital systems, Pulse code modulation, Data compression, Multiplexing, Multichannel communications, Tropospheric scatter communications, Signal processing, Coders, Bandwidth, Compression

Subject Categories : Radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE