Home // International Journal On Advances in Telecommunications, volume 10, numbers 3 and 4, 2017 // View article

A Practical Overview of Recursive Least-Squares Algorithms for Echo Cancellation

Authors:
Camelia Elisei-Iliescu
Constantin Paleologu
Jacob Benesty
Cristian Stanciu
Cristian Anghel
Silviu Ciochina

Keywords: Adaptive filters; Echo cancellation; Recursive least-squares (RLS) algorithm; Variable forgetting factor RLS (VFF-RLS); Variable regularized RLS (VR-RLS).

Abstract:
Due to its fast convergence rate, the recursive least-squares (RLS) algorithm is very popular in many applications of adaptive filtering. However, the computational complexity of this algorithm represents a major limitation in some applications that involve long filters, like echo cancellation. Moreover, the specific features of this application require good tracking capabilities and double-talk robustness for the adaptive algorithm, which further imply an optimization process on its parameters. In the case of most RLS-based algorithms, the performance can be controlled in terms of two main parameters, i.e., the forgetting factor and the regularization term. In this paper, we outline the influence of these parameters on the overall performance of the RLS algorithm and present several solutions to control their behavior, taking into account the specific requirements of echo cancellation application. The resulting variable forgetting factor RLS (VFF-RLS) and variable-regularized RLS (VR-RLS) algorithms could represent appealing solutions for real-world scenarios, as indicated by simulations performed in the context of both network and acoustic echo cancellation.

Pages: 96 to 104

Copyright: Copyright (c) to authors, 2017. Used with permission.

Publication date: December 31, 2017

Published in: journal

ISSN: 1942-2601