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  • Research Article
  • Open Access

A Novel Efficient Cluster-Based MLSE Equalizer for Satellite Communication Channels with -QAM Signaling

  • 1Email author,
  • 2,
  • 3 and
  • 2
EURASIP Journal on Advances in Signal Processing20062006:034343

  • Received: 24 April 2005
  • Accepted: 18 February 2006
  • Published:


In satellites, nonlinear amplifiers used near saturation severely distort the transmitted signal and cause difficulties in its reception. Nevertheless, the nonlinearities introduced by memoryless bandpass amplifiers preserve the symmetries of the -ary quadrature amplitude modulation ( -QAM) constellation. In this paper, a cluster-based sequence equalizer (CBSE) that takes advantage of these symmetries is presented. The proposed equalizer exhibits enhanced performance compared to other techniques, including the conventional linear transversal equalizer, Volterra equalizers, and RBF network equalizers. Moreover, this gain in performance is obtained at a substantially lower computational cost.


  • Information Technology
  • Computational Cost
  • Quantum Information
  • Amplitude Modulation
  • Communication Channel

Authors’ Affiliations

Department of Statistics and Insurance Science, University of Piraeus, 80 Karaoli & Dimitriou Street, Piraeus, 185 34, Greece
Department of Informatics and Telecommunications, University of Athens, Panepistimioupolis, Ilissia, Athens, 157 84, Greece
Institute for Digital Communications, School of Engineering and Electronics, the University of Edinburgh, Kings Buildings, Mayfield Road, Edinburgh, EH9 3JL, United Kingdom


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© Kofidis et al. 2006