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  • Research Article
  • Open Access

Impact of the Gaussian Approximation on the Performance of the Probabilistic Data Association MIMO Decoder

  • 1Email author,
  • 2,
  • 1 and
  • 1
EURASIP Journal on Wireless Communications and Networking20052005:145035

  • Received: 1 March 2005
  • Published:


The probabilistic data association (PDA) decoder is investigated for use in coded multiple-input multiple-output (MIMO) systems and its strengths and weaknesses are determined. The conventional PDA decoder includes two approximations. The received symbols are assumed to be statistically independent and a Gaussian approximation is applied for the interference and noise term. We provide an analytical formula for the exact probability density function (PDF) of the interference and noise term, which is used to discuss the impact of the Gaussian approximation in the presence of a soft-input soft-output channel decoder. The results obtained resemble those obtained for the well-known PDA multiuser detector in coded CDMA systems for which similar investigations have been done before.


  • probabilistic data association
  • MIMO systems
  • stochastic approximation
  • iterative methods
  • interference

Authors’ Affiliations

Information and Coding Theory Lab, Faculty of Engineering, University of Kiel, Kaiserstraβe 2, Kiel, 24143, Germany
Toshiba Research Europe Ltd, Telecommunications Research Laboratory, 32 Queen Square, Bristol, BS1 4ND, UK


© Fricke et al. 2005

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.