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  • Research Article
  • Open Access

Iterative Refinement Methods for Time-Domain Equalizer Design

  • 1,
  • 2,
  • 3, 4 and
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EURASIP Journal on Advances in Signal Processing20062006:043154

  • Received: 1 December 2004
  • Accepted: 2 August 2005
  • Published:


Commonly used time domain equalizer (TEQ) design methods have been recently unified as an optimization problem involving an objective function in the form of a Rayleigh quotient. The direct generalized eigenvalue solution relies on matrix decompositions. To reduce implementation complexity, we propose an iterative refinement approach in which the TEQ length starts at two taps and increases by one tap at each iteration. Each iteration involves matrix-vector multiplications and vector additions with matrices and two-element vectors. At each iteration, the optimization of the objective function either improves or the approach terminates. The iterative refinement approach provides a range of communication performance versus implementation complexity tradeoffs for any TEQ method that fits the Rayleigh quotient framework. We apply the proposed approach to three such TEQ design methods: maximum shortening signal-to-noise ratio, minimum intersymbol interference, and minimum delay spread.


  • Objective Function
  • Communication Performance
  • Delay Spread
  • Minimum Delay
  • Matrix Decomposition

Authors’ Affiliations

Silicon Laboratories, Corporate Headquarters, 7000 West William Cannon Drive, Austin, TX 78735, USA
Schlumberger Sugar Land Product Center, 110 Schlumberger Drive, Sugar Land, TX 77478, USA
Schlumberger Austin Systems Center, 8311 N FM 620 Road, Austin, TX 78726, USA
TICOM Geomatics, 9130 Jollyville Road, Austin, TX 78759, USA
Department of Electrical and Computer Engineering, The University of Texas, Austin, TX 78712-1084, USA


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© Güner Arslan et al. 2006

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.