Patent ID: 8184818

Claim:
A double-talk detector for detecting a double-talk state based on a receiver input signal, a transmitter input signal and a residual signal resultant from eliminating an echo in an echo canceller including an adaptive filter having a filter coefficient to control update of the coefficient, comprising: a noise estimator for finding an estimated power value of near end background noise based on the residual signal; a first transmitter average power calculator for finding an average power value of the transmitter input signal; a first receiver average power calculator for finding an average power value of the receiver input signal; an attenuation value estimator for finding an estimated echo path attenuation value through a predetermined echo path attenuation value estimating process based on the estimated power value of the near end background noise, the average power value of the transmitter input signal and the average power value of the receiver input signal; and a double-talk determiner for detecting a double-talk state based on the estimated echo path attenuation value, the average power value of the transmitter input signal and the average power value of the receiver input signal to control the update of the coefficient.