2nd International Workshop on Physics-Inspired Paradigms in Wireless Communications and Networks

Research Article

Optimal sparse CDMA detection at high load

  • @INPROCEEDINGS{10.1109/WIOPT.2009.5291597,
        author={Jack Raymond},
        title={Optimal sparse CDMA detection at high load},
        proceedings={2nd International Workshop on Physics-Inspired Paradigms in  Wireless Communications and Networks},
        publisher={IEEE},
        proceedings_a={PHYSCOMNET},
        year={2009},
        month={10},
        keywords={Wireless Communication Unit Clause Propagation Optimal Detection},
        doi={10.1109/WIOPT.2009.5291597}
    }
    
  • Jack Raymond
    Year: 2009
    Optimal sparse CDMA detection at high load
    PHYSCOMNET
    IEEE
    DOI: 10.1109/WIOPT.2009.5291597
Jack Raymond1,*
  • 1: School of Physics Hong Kong University of Science and Technology Hong Kong,
*Contact email: jack.raymond@physics.org

Abstract

Balancing efficiency of bandwidth use and complexity of detection involves choosing a suitable load for a multi-access channel. In the case of synchronous CDMA, with random codes, it is possible to demonstrate the existence of a threshold in the load beyond which there is an apparent jump in computational complexity. At small load unit clause propagation can determine a jointly optimal detection of sources on a noiseless channel, but fails at high load. Analysis provides insight into the difference between the standard dense random codes and sparse codes, and the limitations of optimal detection in the sparse case.