| 摘要 |
The invention relates to a method of coding a sampled speech signal vector (s(n)) in an analysis-by-synthesis coding method by forming an optimum excitation vector comprising a linear combination of a code vector from a fixed code book (12) and a long term predictor vector. A first estimate of the long term predictor vector is formed in an open loop analysis (22, 24, 30, 32, 34, 36). A second estimate of the long term predictor vector is formed in a closed loop analysis (gL, 14, 16, 20, 22, 24, 28, 34, 36). Finally, each of the first and second estimates are combined in an exhaustive search (gJ, gL, 14, 16, 20, 22, 24, 28, 36) with each code vector of the fixed code book (12) to form that excitation vector that gives the best coding of the speech signal vector (s(n)). |
