On the use of new adaptive subband structures in acoustic echo cancellation

A new family of adaptive structures which employ filter banks or wavelets to decompose the input signal and reduced-order adaptive filters in the subbands is applied to the acoustic echo control problem. Structures with sparse adaptive subfiltcrs and no down-sampling of the subband signals, as well as structures with critical sampling of the subband signals, arc investigated. Both types of structures yield exact modeling of FIR systems. Computer simulations arc presented to illustrate the convergence behavior of the adaptive subband structures investigated in the paper for acoustic echo cancellation.