Patent ID: 7536007

Claim:
A method comprising: generating a first finite-impulse response (FIR) error signal by differencing a conditioned return signal and an input signal filtered by a first adaptive FIR filter, wherein the first adaptive FIR filter comprises at least one feed-forward gain adapted to be adjusted via a first FIR adaptation mechanism and wherein the first FIR adaptation mechanism is adapted to receive the generated first FIR error signal; generating a first infinite impulse response (IIR) error signal by differencing the conditioned return signal and the input signal filtered by a first adaptive IIR filter wherein the first adaptive IIR filter comprises at least one feed-forward gain and at least one feedback gain adapted to be adjusted via a first IIR adaptation mechanism and wherein the first IIR adaptation mechanism is adapted to receive the generated first IIR error signal; and selecting a signal from a group of filtered input signals comprising the input signal filtered by the first adaptive FIR filter and the input signal filtered by the first adaptive IIR filter, wherein the conditioned return signal is a return signal tested to determine a double talk state.