• DocumentCode
    2647470
  • Title

    Exact and approximated expressions of the log-likelihood ratio for 16-QAM signals

  • Author

    Allpress, Steve ; Luschi, Carlo ; Felix, Steve

  • Author_Institution
    Icera Inc., Bristol, UK
  • Volume
    1
  • fYear
    2004
  • fDate
    7-10 Nov. 2004
  • Firstpage
    794
  • Abstract
    This paper discusses the exact and approximate calculation of the bit log-likelihood ratio (LLR) for a 16-QAM signal. In particular, we introduce a new modified max function, which allows for an effective implementation of the LLR formula. The results of the paper are applicable to 16-QAM soft-demapping in digital receivers that perform soft decision decoding or iterative decoding.
  • Keywords
    iterative decoding; quadrature amplitude modulation; radio receivers; 16-QAM signal; LLR; bit log-likelihood ratio; digital receivers; iterative decoding; modified max function; quadrature amplitude modulation; soft decision decoding; soft-demapping; Availability; Code standards; Error correction codes; Iterative algorithms; Iterative decoding; Modulation coding; Multiaccess communication; Nonlinear filters; Signal processing; Turbo codes;
  • fLanguage
    English
  • Publisher
    ieee
  • Conference_Titel
    Signals, Systems and Computers, 2004. Conference Record of the Thirty-Eighth Asilomar Conference on
  • Print_ISBN
    0-7803-8622-1
  • Type

    conf

  • DOI
    10.1109/ACSSC.2004.1399245
  • Filename
    1399245