Accession Number : ADD009665

Title :   Multirate Digital Voice Communication Processor.

Descriptive Note : Patent,


Personal Author(s) : Kang,George S ; Fransen,Lawrence J ; Kline,Evans L

Report Date : 18 May 1982

Pagination or Media Count : 11

Abstract : To provide alternative operation at 2.4 or 9.6 Kb/s bit rates, a multirate digital processor generates a data frame of 216 bits representing sync and voice encoded at both rates, with the 2.4 Kb/s embedded as a subset within the frame. Speech signal is transformed by linear prediction into coefficients and residual signals. The coefficients are transmitted similarly at both 2.4 and 9.6 Kb/s rates. However, the residual is processed into a simple pitch/hiss excitation signal for 2.4 Kb/s, but is processed into a Fourier transform of its baseband (250-1500 Hz) for 9.6Kb/s excitation signal transmission.

Descriptors :   *Patents, *Voice communications, *Digital systems, *Processing equipment, Speech, Pulse communications, Data rate, Engineering drawings, Inventions, Signal processing, Fourier transformation

Subject Categories : Voice Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE