Journal of Communications and Networks

The Korean Institute of Commucations and Information Sciences (한국통신학회)
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Butterfly Log-MAP Decoding Algorithm

  • Hou, Jia (Institute of Information & Communication, Chonbuk National University) ;
  • Lee, Moon Ho (Institute of Information & Communication, Chonbuk National University) ;
  • Kim, Chang Joo (Radio Technology research group of ETRI)
  • Published : 2004.09.01
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Abstract

In this paper, a butterfly Log-MAP decoding algorithm for turbo code is proposed. Different from the conventional turbo decoder, we derived a generalized formula to calculate the log-likelihood ratio (LLR) and drew a modified butterfly states diagram in 8-states systematic turbo coded system. By comparing the complexity of conventional implementations, the proposed algorithm can efficiently reduce both the computations and work units without bit error ratio (BER) performance degradation.

Keywords

References

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