Description

Abstract

G.728 speech codec is a low delay ITU standard codec which could provide toll quality speech in 16kb/s. It is specially designed for delay-sensitive applications like satellite telephony, Internet, and mobile networks.

In this thesis, real-time implementation of full duplex G.728 encoder and decoder on TMS320C5402 is presented. Using a combinatorial technique for TMS programming, the programming time and complexity have been decreased to 30% compared with traditional assembly programming. First, a fixed point simulation of the codec algorithm has been programmed in C and it is compiled to assembly using CCS (Code Composer Studio) and manually optimized. Then some of the critical functions regarding MIPS, have been programmed in assembly for achieving real-time implementation. Finally, implementation results have been presented.

Keywords: Speech Coding & Compression, Real Time Implementation, DSP,

references :

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19- DCS G.728 C54x Vocoder,                                                                                            algorithm, http://wwwd.connect.ti.com/dsp/tpcat/tpcodec.nsf/SoftwareForExternal/       EAB728D36C3C916E862569F200542A92.