Patent Document ID: 20090116638
Application ID: 11917764
Patent Status: 0

Claim One:
1. A method for adaptive echo cancellation, comprising: configuring an adaptive foreground filter to apply to a block of data including a sparse impulse response to generate a foreground filtered response; calculating an echo return loss responsive to the foreground filtered response; identifying the location of one or more peaks repetitively in the 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; and calculating an echo return loss responsive to the background filtered sparse impulse response, wherein when a peak is confirmed and when the echo return loss responsive to the background filter exceeds the echo return loss responsive to the foreground filter the coefficients from the adaptive foreground filter are replaced by the coefficients from the background filter to generate a modified foreground filter.