Patent ID: 7107303

Claim:
An echo canceller, comprising: an adaptive digital filter that generates an estimated echo signal {circumflex over (z)}[k] in response to (i) a sampled input data sequence x[k] and (ii) an error signal sequence e[k] indicative of the difference between a signal sequence y[k] and the estimated echo signal {circumflex over (z)}[k], said adaptive filter includes N filter taps that each provide an associated tap output signal, wherein said adaptive digital filter generates said estimated echo signal {circumflex over (z)}[k] using said associated tap output signals from M of said N filter taps selected in response to a time delay estimate signal, and said adaptive filter computes filter coefficients for each of said M of said N filter taps using said associated tap output signals from said M of said N filter; a time delay estimator responsive to said sequence x[k] and said sequence y[k], that estimates at least one delay within said sequence x[k], and provides said time delay estimate which is indicative of the location of said at least one delay within said sequence x[k]; and a summer that computes the difference between said signal sequence y[k] and said estimated echo signal {circumflex over (z)}[k] and provides an output signal indicative thereof.