The Fourth Generation Wireless Communications and Beyond

Research Article

Cross-Layer Optimization for OFDMA System with Imperfect CSIT in Quasi Static Channel

  • @INPROCEEDINGS{10.1109/CHINACOM.2008.4685123,
        author={Vincent Kin Nang Lau and Vincent Kin Nang Lau and Wing Kwan Ng and David Shui Wing Hui and Wing Kwan Ng and David Shui Wing Hui and Bin Chen},
        title={Cross-Layer Optimization for OFDMA System with Imperfect CSIT in Quasi Static Channel},
        proceedings={The Fourth Generation Wireless Communications and Beyond},
        publisher={IEEE},
        proceedings_a={CHINACOM2008-INDUSTRIAL},
        year={2008},
        month={11},
        keywords={OFDMA slow fading channel outage probability scheduling  extreme value theory},
        doi={10.1109/CHINACOM.2008.4685123}
    }
    
  • Vincent Kin Nang Lau
    Vincent Kin Nang Lau
    Wing Kwan Ng
    David Shui Wing Hui
    Wing Kwan Ng
    David Shui Wing Hui
    Bin Chen
    Year: 2008
    Cross-Layer Optimization for OFDMA System with Imperfect CSIT in Quasi Static Channel
    CHINACOM2008-INDUSTRIAL
    IEEE
    DOI: 10.1109/CHINACOM.2008.4685123
Vincent Kin Nang Lau1,*, Vincent Kin Nang Lau2,*, Wing Kwan Ng1,*, David Shui Wing Hui1,*, Wing Kwan Ng2,*, David Shui Wing Hui2,*, Bin Chen3,*
  • 1: Department of Electronic and Computer Engineering The Hong Kong University of Science and Technology
  • 2: Department of Electronic and Computer Engineering
  • 3: The Hong Kong University of Science and Technology Huawei Technologies Co., Ltd
*Contact email: eeknlau@ee.ust.hk, eeknlau@ee.ust.hk, eekwan@ust.hk, davidhui@ust.hk, yeekwan@ust.hk, davidhui@ust.hk, binchen@huawei.com

Abstract

Asymptotic performance analysis of orthogonal frequency division multiple access (OFDMA) is conducted in this work. We take a cross-layer approach and analyze how the system performance scale with some important parameters such as number of user, CSIT quality and order of diversity. It is well studied that system goodput scale with number of user $K$ in the order of ${cal O}(log log K)$ due to multiuser diversity (emph{system goodput gain}) under perfect CSIT assumption. However, in quasi static fading channels with imperfect CSIT, channel outage happens even if capacity achieving coding is applied at the base station. In this case, cross-layer scheduler can protect the packet by increasing the order of diversity ({em packet outage diversity}) . So, there is a trade-off between system goodput gain and packet outage diversity.