Patent ID: 8712068

Claim:
A method for acoustic echo cancellation (AEC), comprising: transforming an input signal to the frequency domain to provide a frequency domain input signal; adaptive filtering the frequency domain input signal to provide an adaptive filtered output signal; transforming the input signal and the error signal from the time domain into the spectral domain to provide a frequency domain input signal and a frequency domain error signal; delaying the frequency domain input signal to generate multiple differently delayed input signals in the frequency domain; filtering each of the multiple differently delayed input signals in the frequency domain according to the frequency domain error signal; summing the filtered differently delayed input signals in the frequency domain to generate the approximated output signal in the frequency domain; and transforming the approximated output signal from the frequency domain into the time domain, where the adaptive filtering comprises applying a sequential constraint algorithm such that a constraint is applied only once for at least one of the delayed input signals in the frequency domain, and where the respective delayed input signal to which the constraint is applied to changes sequentially in the subsequent block.