Patent ID: 7613291

Claim:
A method for use by an echo canceller having a foreground adaptive filter and a background adaptive filter to detect an echo path change and adjust to said echo path change, said method comprising: determining a first bulk delay of an echo signal using said foreground adaptive filter, said foreground adaptive filter being a SPARSE filter; configuring said foreground adaptive filter to an open-loop mode; canceling said echo signal from a local-end signal based on said first bulk delay using said foreground adaptive filter, wherein canceling said echo signal from said local-end signal generates an error signal; feeding said error signal to both said foreground adaptive filter and said background adaptive filter; determining a second bulk delay of said echo signal using said background adaptive filter, said background adaptive filter being a SPARSE filter; configuring said foreground adaptive filter to a closed-loop mode and continuing to cancel said echo signal from said local-end signal based on said first bulk delay; configuring said background adaptive filter to said open-loop mode; measuring an echo cancellation performance of said foreground adaptive filter and an echo cancellation performance of said background adaptive filter; and changing parameters of said foreground adaptive filter if said measuring determines that said echo cancellation performance of said background adaptive filter is better than said echo cancellation performance of said foreground adaptive filter.