APPARATUS AND METHOD FOR CODEC SIGNAL IN A COMMUNICATION SYSTEM

摘要

PURPOSE: A signal codec device in a communication system and a method thereof are provided to normally encode and decode voice and audio signals through a wideband codec and a narrowband codec by adjusting a harmonic element of an adaptive codebook excitation signal according to a frequency band without transmitting additional information. CONSTITUTION: A first generating unit(110) generates an fixed codebook excitation signal by using a pulse index for a voice signal. A second generating unit(120) generates a first adaptive codebook excitation signal by using a pitch index for the voice signal. A first multiplying unit(130) generates a fixed codebook signal by multiplying the fixed codebook excitation signal by a fixed codebook gain. A second multiplying unit(140) generates a first codebook signal by multiplying the first adaptive codebook excitation signal by a first adaptive codebook gain. An adding unit(150) generates a synthesis filter excitation signal by adding up the fixed codebook signal and the first adaptive codebook signal. [Reference numerals] (110) First generating unit; (120) Second generating unit