Spectrum selective nonlinear echo suppression based on the amount of linear echo cancellation

When acoustic echo cancellation or suppression is applied to hands-free communications in cellular phones, it is important for it to be robust against echo path variation and to suppress highly nonlinear echo at low cost. This paper proposes the spectrum selective nonlinear echo suppression (SS-ES) approach as a solution to these issues. SS-ES is characterized by selecting either a spectrum of the residual signal from an adaptive filter or a spectrum of the sending input signal depending on the contribution from linear echo cancellation in an adaptive filter. In the SS-ES approach, the results of objective evaluation show that the average ERLE is approximately 1.2-2.7 dB, the average LSD is approximately 0.19-0.62 dB, and the PESQ values is approximately 0.36-0.53 better than the conventional methods under conditions of echo path variation and double-talk.