An Improved Error Estimation Algorithm for Stereophonic Acoustic Echo Cancellation Systems

In this paper, we propose an error estimate algorithm (EEA) for stereophonic acoustic echo cancellation (SAEC) that is based on an extension of the set-membership normalized least mean-squares (SM-NLMS) algorithm combined with the affine projection (AP) algorithm. In the EEA, with the minimum error signal fixed, we compute the filter lengths so that the error signal may approximate the minimum error signal. When the echo paths change, the adaptive filter automatically adjusts the filter lengths to the optimum values. We also investigate the difference between the adaptive filter lengths. In contrast with the conclusion in [1]–[6], our simulation results have shown that the filter lengths can be different. Our simulation results also confirm that the EEA is better than SM-NLMS algorithm in terms of echo return loss enhancement.