METHOD FOR ALGEBRAIC CODEBOOK SEARCH OF SPEECH SIGNAL ENCODER AND COMMUNICATION EQUIPMENT HAVING THE SPEECH SIGNAL ENCODER

摘要

PROBLEM TO BE SOLVED: To reduce many memory parts and to decrease the number of memory parts which are requested to perform computing operation by search algorithm. SOLUTION: In an algebraic codebook search method of a speech signal encoder, a time interval including (n) speech signal samplings is divided into an integral number (t) of tracks each having (p) possible pulse positions respectively to compute coefficients of a triangular matrix of a Toeplitz type autocorrelation matrix by preferably using a Code Excited Linear Prediction process and the coefficients are stored in respective areas of a memory while being classified into groups of combinations of adjacent tracks, combinations of non-adjacent tracks, combinations of exactly the same tracks, and coefficients of principal diagonals of the autocorrelation matrix.