Novel reduced-state BCJR algorithms

CM Vithanage, C Andrieu, RJ Piechocki

Research output: Contribution to journalArticle (Academic Journal)

10 Citations (Scopus)
399 Downloads (Pure)


BCJR algorithm is an exact and efficient algorithm to compute the marginal posterior distributions of state variables and pairs of consecutive state variables of a trellis structure. Due to its overwhelming complexity, reduced complexity variations, such as the M-BCJR algorithm, have been developed. In this paper, we propose improvements upon the conventional M-BCJR algorithm based on modified active state selection criteria. We propose selecting the active states based on estimates of the fixed-lag smoothed distributions of the state variables. We also present Gaussian approximation techniques for the low-complexity estimation of these fixed-lag smoothed distributions. The improved performance over the M-BCJR algorithm is shown via computer simulations.
Translated title of the contributionNovel Reduced-State BCJR Algorithms
Original languageEnglish
Pages (from-to)1144 - 1152
Number of pages9
JournalIEEE Transactions on Communications
Issue number6
Publication statusPublished - Jun 2007

Bibliographical note

Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Rose publication type: Journal article

Sponsorship: This work was supported by Toshiba Research
Europe, Ltd., Bristol, U.K.

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  • fading channels
  • state space methods
  • decoding
  • digital communication
  • multiple-input multiple-output (MIMO) systems
  • nonlinear detection
  • signal detection

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