Patent ID: 8135584
Filing Date: 2012-03-13
Classification: G10L

Abstract:
1. A method for generating an excitation signal to excite an audio synthesis filter, comprising: temporally continuously storing sampled excitation values being already generated in an adaptive code book; continuously generating random sampled values by a noise generator; selecting a sequence of the sampled excitation values from the adaptive code book based on an audio basic frequency parameter that predetermines a time interval between a time of the sequence to be selected and current time; and generating the excitation signal by mixing the selected sequence of the sampled excitation values with a random sequence of the random sampled values containing random sampled values of the noise generator at the current time; and wherein if the audio basic frequency parameter is not a whole-number multiple of a sampling interval of a narrowband excitation signal to be generated, intermediate sampled values are inserted between the sampled excitation values or between the random sampled values as a function of the audio basic frequency parameter.