Analysis and optimization of speech coder algorithm for CDMA digital cellular

Abstract

CELP coding is a powerful technique for the realization of high-quality speech coders operating at variable bit rates. The paper describes an implementation of a QCELP coder algorithm for CDMA. In addition, a hardware implementation for improving the speech coding rate of QCELP speech coders is explored. The coder can operate at different bit rates by simply comparing the energy in the frame with the threshold which is based upon an estimate of the background noise level. This research is based upon the design of DSP chips and ASICs for dedicated digital mobile communication applications.<>