Patent ID: 8081753

Claim:
A system for controlling an echo canceller configured to remove echo from a corrupted signal, comprising: a signal indicator configured to indicate periods of near-end signal and to indicate periods of echo only with echo-path change in the corrupted signal based at least in part on a cross-correlation between two signals associated with the echo canceller; and an echo canceller controller configured to control the echo canceller according to indications from the signal indicator, wherein the signal indicator comprises one or more signal discriminators configured to determine a relative influence of the near-end signal compared to the echo in the corrupted signal, wherein the echo canceller controller is configured to control the echo canceller according to indications from the signal indicator by preventing at least one of the echo canceller's one or more adaptive filters from adapting when the signal indicator indicates a period of near-end signal in the corrupted signal; the signal indicator is further configured to indicate periods of no near-end signal and no echo and periods of echo only without echo-path change in the corrupted signal; the echo canceller controller is configured to control the echo canceller according to the indications from the signal indicator by preventing at least one of the echo canceller's one or more adaptive filters from adapting when the signal indicator indicates a period of no near-end signal and no echo in the corrupted signal and by allowing at least one of the echo canceller's one or more adaptive filters to adapt when the signal indicator indicates a period of echo only without echo-path change or a period of echo only with echo-path change in the corrupted signal; the signal indicator comprises one or more cross-correlators configured to cross-correlate the corrupted signal with the echo canceller's error signal, and one or more detectors configured to facilitate indicating periods of no echo and no near-end signal in the corrupted signal; and the one or more cross-correlators are implemented at a frequency bin level and the one or more signal discriminators comprise one signal discriminator configured at the frame level and the one or more detectors comprise one detector configured at the frame level.