A proportionate adaptive algorithm with variable partitioned block length for acoustic echo cancellation

Due to the nature of an acoustic enclosure, the early part (i.e., direct path and early reflections) of the acoustic echo path is often sparse while the late reverberant part of the acoustic path is normally dispersive. In order to account for this structure within the acoustic impulse response when performing acoustic echo cancellation, we propose an adaptive filter that consists of two time-domain partition blocks, with adaptive block partitioning, such that different adaptive algorithms can be used for each block. Specifically, the improved proportionate normalized least-mean-square (IPNLMS) algorithm is used. Simulation results show that the proposed variable length partitioned block IPNLMS (VLPB-IPNLMS) algorithm works well in both sparse and dispersive circumstances and in practical applications involving time-varying systems.