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  • Research Article
  • Open Access

Efficient Bidirectional DFE for Doubly Selective Wireless Channels

EURASIP Journal on Advances in Signal Processing20062006:070572

  • Received: 1 June 2005
  • Accepted: 7 November 2005
  • Published:


The bidirectional decision feedback equalizer (DFE) performs two equalizations, one on the received signal and one on its time-reversed version. In this paper, we apply the bidirectional DFE to wireless transmissions on rapidly time-varying dispersive channels and we propose an efficient implementation obtained by implementing the feedforward filter in the frequency domain. The feedback filter is adapted to the channel variations within one block and we propose a simplified design of the feedback filter coefficients based on a polynomial model of channel variations. Simulations performed on time-varying channels show that the proposed structure significantly outperforms existing architectures.


  • Information Technology
  • Frequency Domain
  • Receive Signal
  • Quantum Information
  • Wireless Channel

Authors’ Affiliations

Department of Information Engineering, University of Padova, Via Gradenigo 6/B, Padova, 35131, Italy


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© Tomasin 2006