Open Access

A Robust Parametric Technique for Multipath Channel Estimation in the Uplink of a DS-CDMA System

  • Vassilis Kekatos1,
  • Athanasios A Rontogiannis2 and
  • Kostas Berberidis1Email author
EURASIP Journal on Wireless Communications and Networking20062006:047938

DOI: 10.1155/WCN/2006/47938

Received: 9 November 2004

Accepted: 28 December 2005

Published: 7 March 2006

Abstract

The problem of estimating the multipath channel parameters of a new user entering the uplink of an asynchronous direct sequence-code division multiple access (DS-CDMA) system is addressed. The problem is described via a least squares (LS) cost function with a rich structure. This cost function, which is nonlinear with respect to the time delays and linear with respect to the gains of the multipath channel, is proved to be approximately decoupled in terms of the path delays. Due to this structure, an iterative procedure of 1D searches is adequate for time delays estimation. The resulting method is computationally efficient, does not require any specific pilot signal, and performs well for a small number of training symbols. Simulation results show that the proposed technique offers a better estimation accuracy compared to existing related methods, and is robust to multiple access interference.

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Authors’ Affiliations

(1)
Department of Computer Engineering and Informatics and Research Academic Computer Technology Institute, University of Patras
(2)
Institute of Space Applications and Remote Sensing, National Observatory of Athens

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Copyright

© Vassilis Kekatos 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.