A 6.6 kb/s CELP speech coder: high performance for GSM half-rate system
Hongmei Ai, X. L. Lau Yang, Dajun Lu · 2002
The paper describes a 6.6 kb/s speech coder with high performance, suitable for the GSM half-rate system. The coder is based on the codebook excited linear prediction (CELP) technique. Line spectrum pair (LSP) representation is introduced. Fast stochastic codebook search procedures based on a linear-shifted Gaussian noise sequence are proposed and a detailed description of gain quantizers and adaptive post-filter is presented. This coder structure also exhibits good performance at a data rate as low as 4.8 kb/s.>