2nd International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications

Research Article

Soft-demodulation of Transform Domain Communication System Signals

  • @INPROCEEDINGS{10.1109/CROWNCOM.2007.4549828,
        author={Chuan Han and Jun Wang and Ning Liu and Shuping Gong and Shaoqian Li},
        title={Soft-demodulation of Transform Domain Communication System Signals},
        proceedings={2nd International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications},
        publisher={IEEE},
        proceedings_a={CROWNCOM},
        year={2008},
        month={6},
        keywords={Cognitive radio transform domain communication system soft-demodulation},
        doi={10.1109/CROWNCOM.2007.4549828}
    }
    
  • Chuan Han
    Jun Wang
    Ning Liu
    Shuping Gong
    Shaoqian Li
    Year: 2008
    Soft-demodulation of Transform Domain Communication System Signals
    CROWNCOM
    IEEE
    DOI: 10.1109/CROWNCOM.2007.4549828
Chuan Han1,*, Jun Wang1,*, Ning Liu1, Shuping Gong1,*, Shaoqian Li1,*
  • 1: National Key Laboratory of Communications University of Electronic Science and Technology of China Chengdu, Sichuan, 610054, P.R. China
*Contact email: chuan.han.comm@gmail.com, junwang@uestc.edu.cn, shuping81@tom.com, lsq@uestc.edu.cn

Abstract

Cognitive radio (CR) has become one promising solution to the shortage of spectrum resources and transform domain communication system (TDCS) has been proposed as one candidate transmission technique of CR, especially as a transmission candidate of signaling in the CR context. While in most modern communication systems soft-demodulation is concatenated with soft-decision decoding to achieve high performances, current TDCS cannot output soft information. In this work, the soft-demodulation algorithm of TDCS signals in fading channels and its efficient IFFT-based implementation are proposed. This implementation only introduces negligible complexity increase in the receiver; however, it brings performance improvement and makes it possible to efficiently and iteratively soft-decode coded data. Simulation results of both perfect and practical channel estimation in the IEEE 802.22 Profile C channel show that the proposed method outperforms the hard-decision demodulation method, especially in the high- SNR-region.