| 摘要 |
PROBLEM TO BE SOLVED: To overcome the problem with a conventional echo cancellation device, wherein the adaptive filter lengths of two pseudo echo paths cannot be set separately because the amount of respective errors of the reception signals of two channels cannot be measured. SOLUTION: In an echo cancellation technique relating to this invention, when a difference of values corresponding to coefficients in expressing the transmission characteristics of an echo path, which are determined by the positional relationship of a speaker for reproducing the reception signals of two channels and a microphone for collecting the reproducing sound, by a filter is larger than a threshold, a filter length is determined so that the adaptive filter length corresponding to the larger value becomes longer than the adaptive filter length corresponding to the smaller value, and an adaptive filter coefficient corresponding to the reception signals of the respective channels is sequentially updated using a present adaptive filter coefficient, the reception signals of the two channels and error signals on the basis of the determined filter length. COPYRIGHT: (C)2011,JPO&INPIT |
