Functional link based architectures for nonlinear acoustic echo cancellation

This paper introduces a collaborative architecture for nonlinear acoustic echo cancellation. This system is achieved linearly combining a standard linear filter and a functional link (FL) nonlinear filter. The FL filter is composed of merely nonlinear elements thus acting like a pure nonlinear kernel and modeling at best a nonlinear path. A more robust architecture is further introduced in which the FL filter is adaptively combined with an all-zero kernel (AZK) avoiding any gradient noise when nonlinearities are negligible. Experimental results show that proposed architectures present improved performance compared with other nonlinear echo cancellers notwithstanding the nonlinearity level in the echo path.