Efficient Multichannel NLMS Implementation for Acoustic Echo Cancellation

  • Fredric Lindstrom
  • Christian Schüldt
  • Ingvar Claesson
Open Access
Research Article
Part of the following topical collections:
  1. Adaptive Partial-Update and Sparse System Identification


An acoustic echo cancellation structure with a single loudspeaker and multiple microphones is, from a system identification perspective, generally modelled as a single-input multiple-output system. Such a system thus implies specific echo-path models (adaptive filter) for every loudspeaker to microphone path. Due to the often large dimensionality of the filters, which is required to model rooms with standard reverberation time, the adaptation process can be computationally demanding. This paper presents a selective updating normalized least mean square (NLMS)-based method which reduces complexity to nearly half in practical situations, while showing superior convergence speed performance as compared to conventional complexity reduction schemes. Moreover, the method concentrates the filter adaptation to the filter which is most misadjusted, which is a typically desired feature.


Acoustics Adaptive Filter Complexity Reduction Identification Perspective Reverberation Time 
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Copyright information

© Fredric Lindstrom et al. 2007

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Authors and Affiliations

  • Fredric Lindstrom
    • 1
  • Christian Schüldt
    • 2
  • Ingvar Claesson
    • 2
  1. 1.Konftel ABResearch and DevelopmentUmeaSweden
  2. 2.Department of Signal ProcessingBlekinge Institute of TechnologyRonnebySweden

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