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  • Research Article
  • Open Access

Rate-Optimal Multiuser Scheduling with Reduced Feedback Load and Analysis of Delay Effects

  • 1Email author,
  • 2,
  • 1 and
  • 3
EURASIP Journal on Wireless Communications and Networking20062006:036424

  • Received: 30 September 2005
  • Accepted: 26 May 2006
  • Published:


We propose a feedback algorithm for wireless networks that always collects feedback from the user with the best channel conditions and has a significant reduction in feedback load compared to full feedback. The algorithm is based on a carrier-to-noise threshold, and closed-form expressions for the feedback load as well as the threshold value that minimizes the feedback load have been found. We analyze two delay scenarios. The first scenario is where the scheduling decision is based on outdated channel estimates, and the second scenario is where both the scheduling decision and the adaptive modulation are based on outdated channel estimates.


  • Information System
  • Wireless Network
  • System Application
  • Channel Estimate
  • Channel Condition


Authors’ Affiliations

Department of Electronics and Telecommunications, Norwegian University of Science and Technology, Trondheim, 7491, Norway
Department of Electrical Engineering, Texas A&M University at Qatar (TAMUQ), Education City, P.O. Box 5825, Doha, Qatar
Mobile Communications Department, Eurécom Institute, Sophia Antipolis, 06904, France


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© Vegard Hassel 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.