Patent ID: 7450528
Filing Date: 2008-11-11
Classification: H04B

Abstract:
1. A method of performing echo suppression in a telecommunications system, the method comprising: (A) calculating at least one value representing energy in a plurality of pulse code modulated (PCM) samples of an input speech signal; (B) building a synthetic echo envelope from said values; (C) aggregating said values for the at least one sample over a period of time to form a frame of an aggregate energy value for that period of time; (D) solving a plurality of normal equations for said aggregated values, the plurality of normal equations having a plurality of results; (E) examining the results to determine a peak aggregate result, the peak aggregate indicating a time delay and a gain of an echo path; and (F) evaluating each incoming PCM sample against a corresponding output energy result obtained at a determined time delay, and if an input speech energy is determined to be less than a historical output energy scaled by a determined gain, then suppressing echo from the input speech signal.