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Bulletin of the Polish Academy of Sciences Technical Sciences

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Volume 60, Issue 3 (Dec 2012)


A comparison of algorithms for separation of synchronous subspaces

M. Almeida
  • Corresponding author
  • Instituto de Telecomunicac¸ ˜oes, Instituto Superior T´ecnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal / Department of Information and Computer Science, Aalto University, F1–00076 Aalto, Finland
  • Email:
/ J. Bioucas-Dias
  • Instituto de Telecomunicaç˜oes, Instituto Superior Técnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
/ R. Vigário
  • Instituto de Telecomunicaç˜oes, Instituto Superior Técnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
/ E. Oja
  • Department of Information and Computer Science, Aalto University, F1–00076 Aalto, Finland
Published Online: 2012-12-22 | DOI: https://doi.org/10.2478/v10175-012-0057-y


Independent Subspace Analysis (ISA) consists in separating sets (subspaces) of dependent sources, with different sets being independent of each other. While a few algorithms have been proposed to solve this problem, they are all completely general in the sense that they do not make any assumptions on the intra-subspace dependency. In this paper, we address the ISA problem in the specific context of Separation of Synchronous Sources (SSS), i.e., we aim to solve the ISA problem when the intra-subspace dependency is known to be perfect phase synchrony between all sources in that subspace. We compare multiple algorithmic solutions for this problem, by analyzing their performance on an MEG-like dataset.

Keywords : phase-locking; synchrony; source separation; subspaces; Independent Component Analysis (ICA); Independent Subspace Analysis (ISA); magnetoencephalogram (MEG).

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About the article

Published Online: 2012-12-22

Published in Print: 2012-12-01

Citation Information: Bulletin of the Polish Academy of Sciences: Technical Sciences, ISSN (Print) 0239-7528, DOI: https://doi.org/10.2478/v10175-012-0057-y. Export Citation

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