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  • Research Article
  • Open Access

On the Use of Padé Approximation for Performance Evaluation of Maximal Ratio Combining Diversity over Weibull Fading Channels

EURASIP Journal on Wireless Communications and Networking20062006:058501

  • Received: 1 April 2005
  • Accepted: 11 October 2005
  • Published:


We use the Padé approximation (PA) technique to obtain closed-form approximate expressions for the moment-generating function (MGF) of the Weibull random variable. Unlike previously obtained closed-form exact expressions for the MGF, which are relatively complicated as being given in terms of the Meijer G-function, PA can be used to obtain simple rational expressions for the MGF, which can be easily used in further computations. We illustrate the accuracy of the PA technique by comparing its results to either the existing exact MGF or to that obtained via Monte Carlo simulations. Using the approximate expressions, we analyze the performance of digital modulation schemes over the single channel and the multichannels employing maximal ratio combining (MRC) under the Weibull fading assumption. Our results show excellent agreement with previously published results as well as with simulations.


  • Monte Carlo Simulation
  • Fading Channel
  • Modulation Scheme
  • Exact Expression
  • Approximate Expression


Authors’ Affiliations

Department of Electrical Engineering, Center for Wireless Communications, The University of Mississippi, University, MS 38677-1848, USA


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© M. H. Ismail and M. M. Matalgah 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.