20090116638 | Systems and Methods for Adaptive Echo Cancellation - An echo canceller comprises foreground and background filters. The background filter locates and confirms peaks, defines active regions centered about the confirmed peaks and updates coefficients of the foreground filter when the background filter is more effective than the foreground filter A method for improved adaptive echo cancellation comprises configuring a foreground filter, calculating an echo-return loss responsive to the foreground filter, identifying the location of one or more peaks repetitively in a block of data in a background filter, confirming one or more identified peaks over a defined number of blocks before defining an active region equally about the identified peaks in the background filter, filtering the sparse impulse response responsive to the active regions, calculating an echo-return loss responsive to the background filter, and updating the foreground filter when the background filter includes a more effective set of filter coefficients. | 05-07-2009 |