Full proportionate functional link adaptive filters for nonlinear acoustic echo cancellation

Nonlinear acoustic echo cancellation (NAEC) can be mainly addressed by solving two different sub-problems: the estimation of the acoustic impulse response and the modeling of the nonlinearities rebounding in it, mostly caused by the electroacoustic chain. Both the modeling processes share an important characteristic: the majority of the parameters to be estimated are very close to zero, with only a small fraction of them having non-negligible magnitude. In this paper, a novel NAEC model is proposed taking into account both the above sub-problems under a joint optimization problem. In particular, the proposed model involves two separate and parallel filters, one mainly focusing on the estimation of the acoustic impulse response (AIR) and the other one aiming at the nonlinear modeling. In order to optimize the modeling processes, both the filters are adapted by using a joint proportionate algorithm. Experimental results prove the effectiveness of the proposed model in NAEC problems.