Performance Analysis of the Gradient Comparator LMS Algorithm

Bijit Kumar Das; Mrityunjoy Chakraborty

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arXiv · 1605.02877

Performance Analysis of the Gradient Comparator LMS Algorithm

Bijit Kumar Das·Mrityunjoy Chakraborty

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Abstract

The sparsity-aware zero attractor least mean square (ZA-LMS) algorithm manifests much lower misadjustment in strongly sparse environment than its sparsity-agnostic counterpart, the least mean square (LMS), but is shown to perform worse than the LMS when sparsity of the impulse response decreases. The reweighted variant of the ZA-LMS, namely RZA-LMS shows robustness against this variation in sparsity, but at the price of increased computational complexity. The other variants such as the l 0 -LMS and the improved proportionate normalized LMS (IPNLMS), though perform satisfactorily, are also computationally intensive. The gradient comparator LMS (GC-LMS) is a practical solution of this trade-off when hardware constraint is to be considered. In this paper, we analyse the mean and the mean square convergence performance of the GC-LMS algorithm in detail. The analyses satisfactorily match with the simulation results.

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Bijit Kumar Das, Mrityunjoy Chakraborty. 2016-05-10. Performance Analysis of the Gradient Comparator LMS Algorithm. https://arxiv.org/abs/1605.02877

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