An improved mu-law proportionate NLMS algorithm

In this paper, we propose an algorithm to improve the perfor-mance of the mu-law PNLMS algorithm (MPNLMS) for non-sparse impulse responses. Although the existing MPNLMS algorithm was recently proposed to achieve optimal propor-tionate step size for both large and small tap weights, it con-verges even slower than conventional NLMS algorithm for dispersive channels. The proposed approach adaptively esti-mates the sparsity of the impulse response to be identified. Then the estimation of this sparsity is incorporated into the IPNLMS algorithm to accordingly adjust its parameters. Sim-ulation results verify the effectiveness of the proposed algo-rithm. Index Terms — Adaptive signal processing, adaptive fil-ters, NLMS algorithm, PNLMS algorithm, MPNLMS algo-rithm, acoustic signal processing 1