SYSTEM AND METHOD FOR AVOIDING FALSE CONVERGENCE DUE TO PRESENCE OF TONES IN TIME-DOMAIN ECHO CANCELLATION PROCESSING

摘要

PROBLEM TO BE SOLVED: To provide a system and a method for avoiding false convergence due to the presence of a tone, in time-domain echo cancellation.;SOLUTION: The system for avoiding false convergence in an echo canceler, having an adaptive step size controlled for converge a set of filter tap values and an adaptive filter for estimating the channel response over the entire operating frequency range comprises a means for determining the content of spectrum of a set of filter tap values, and means for controlling the adaptive step size of the adaptive filter, depending on the content of spectrum of a set of filter tap values. The means for controlling the adaptive step size comprises a means for decreasing the adaptive step size, when the content of spectrum indicates a state possibly causing false convergence, and means for increasing the adaptive step size subsequent to decrease thereof.;COPYRIGHT: (C)2003,JPO