PROCEDE ET DISPOSITIF D'EVALUATION DE L'ENERGIE DU SIGNAL DE PAROLE PAR SOUS BANDE POUR VOCODEUR BAS DEBITS

摘要

The method involves performing analysis of signals transmitted between transmission and reception vocoders to predict the linear response characteristic. A filter in the transmitter circuit (3) has an impulse response which is the inverse of the receiver synthesis filter response. The receiver synthesis filter is preferably a linear phase digital filter. The filter estimates (4) the residual frequency spectrum. The estimate allows the receiver vocoder impulse response filter to be set to the optimum frequency response curve to reduce the residual spectrum frequency.