Zero attracting proportionate normalized subband adaptive filtering technique for feedback cancellation in hearing aids

Abstract

Acoustic feedback cancelers (AFC) employing normalized subband adaptive filtering (NSAF) in conjunction with proportionate gain allocation strategy (PNSAF) have been utilized to mitigate the effect of acoustic feedback in hearing aids. However, it was found to exhibit fast convergence at the initial stage whereas slowing down the convergence at later phase of the adaptation process. In an endeavor to overcome this, l 1 norm-based penalty element is incorporated with the PNSAF algorithm proposing a new zero attracting PNSAF (ZA-PNSAF) based AFC system. Further, re-weighted ZA-PNSAF (RZA-PNSAF) algorithm is newly introduced to address the varying sparsity conditions. The efficacy of the proposed method is demonstrated by higher maximum stable gain (MSG) (3�5 dB) and PESQ (perceptual evaluation of speech quality) values obtained over existing algorithms. In addition, the convergence and mean square deviation (MSD) analysis of the proposed algorithm are also carried out. Analysis of the ZA-PNSAF algorithm is validated through comparison of the simulated and analytical MSD values. � 2019 Elsevier Ltd