Patent ID: 7711108

Claim:
A method of adjusting an echo canceller, said method comprising: obtaining a first cross-correlation between a far-end signal and an error signal, wherein said error signal is generated by subtracting an output signal of an adaptive filter from a local-end signal including an echo signal, wherein said adaptive filter utilizes said far-end signal to generate the output signal, and wherein said first cross-correlation is indicative of adequacy of cancellation of said echo signal; determining whether said first cross-correlation is above a pro-determined threshold; relocating said adaptive filter by a few samples if said determining determines that said first cross-correlation is above said pre-determined threshold indicative of said echo signal not being cancelled adequately; calculating a first improvement indicator parameter, wherein said first improvement indicator parameter is calculated after said relocating said adaptive filter by said few samples; and determining whether said first improvement indicator parameter indicates a performance improvement by said adaptive filter after said relocating said adaptive filter by said few samples; wherein said first cross-correlation is defined by: C =  ∑ 0 N - 1 ⁢ ⁢ e ⁡ ( n ) · x ⁡ ( n - k )  ∑ 0 N - 1 ⁢ ⁢ e 2 ⁡ ( n ) ⁢ ∑ 0 N - 1 ⁢ ⁢ x 2 ⁡ ( n - k ) ⁢ ⁢ where , 0 < C < 1 wherein C designates said first cross-correlation, x(n) designates said far-end signal, e(n) designates said error signal.