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Open Access

PSD-Constrained PAR Reduction for DMT/OFDM

  • Niklas Andgart1Email author,
  • Brian S. Krongold2,
  • Per Ödling1,
  • Albin Johansson3 and
  • Per Ola Börjesson1
EURASIP Journal on Advances in Signal Processing20042004:836923

Received: 28 February 2003

Published: 7 September 2004


Common to all DMT/OFDM systems is a large peak-to-average ratio (PAR), which can lead to low power efficiency and nonlinear distortion. Tone reservation uses unused or reserved tones to design a peak-canceling signal to lower the PAR of a transmit block. In DMT ADSL systems, the power allocated to these tones may be limited due to crosstalk issues with many users in one twisted pair bundle. This PSD limitation not only limits PAR reduction ability, but also makes the optimization problem more challenging to solve. Extending the recently proposed active set tone reservation method, we develop an efficient algorithm with performance close to the optimal solution.

Keywords and phrases

peak-to-average ratiotone reservationOFDMDMT

Authors’ Affiliations

Signal Processing Group, Department of Information Technology, Lund University, Lund, Sweden
Australian Research Council (ARC) Special Research Centre for Ultra-Broadband Information Networks, University of Melbourne, Victoria, Australia
Ericsson AB, Stockholm, Sweden


© Andgart et al. 2004

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.