Conference Paper

Variable step-size NLMS algorithms designed for echo cancellation

Univ. Politeh. of Bucharest, Bucharest, Romania
DOI: 10.1109/ACSSC.2009.5469916 Conference: Signals, Systems and Computers, 2009 Conference Record of the Forty-Third Asilomar Conference on
Source: IEEE Xplore

ABSTRACT A major issue in echo cancellation is to recover the near-end signal from the error signal of the adaptive filter. In this paper, we use this requirement in order to design a family of variable step-size normalized least-mean-square (VSS-NLMS) algorithms. The main parameter that is needed within these algorithms is the near-end signal power estimate. Several solutions for this problem are presented and evaluated in terms of different practical aspects (i.e., available parameters, complexity). Due to their specific characteristic, these VSS-NLMS algorithms are equipped with good robustness features against near-end signal variations (e.g., double-talk) and can be reliable candidates for real-world echo cancellation scenarios.

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