Variable regularisation parameter sign subband adaptive filter

A sign subband adaptive filter (SSAF) for acoustic echo cancellation is proposed, which is derived by minimising the L₁-norm of the subband a posteriori error vector subject to a constraint on the tap-weight vector of the filter. In addition, a variable regularisation parameter (VRP) is introduced to improve the performance of the SSAF. Simulation results are presented to verify the good robustness of the proposed VRP-SSAF against double-talk.