Enhanced Implementation of Max ∗  Operator for Turbo Decoding

  • Dongpei LiuEmail author
  • Hengzhu Liu
  • Li Zhou
Conference paper
Part of the Lecture Notes in Electrical Engineering book series (LNEE, volume 274)


Max ∗  operator is the kernel operation in MAP decoding. An intuitive approximation to the correction term of max ∗  operator is presented. The binary-tree based architecture for multi-variable max ∗  calculation is also suggested. The proposed max ∗  operator provides a good trade off between hardware overhead and logic delay, and can be easily realized in parallel. Simulations on (37,21) turbo code demonstrate that the BER performance of proposed scheme is almost near the optimal Log-MAP algorithm and significantly superior to the Max-Log-MAP algorithm. The proposed enhanced implementation of max ∗  operator has potential applications in turbo decoder.


Max ∗  operator Correction function Turbo decoding Log-MAP algorithm Max-Log-MAP algorithm 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.The Institute of Micro-electronics and Micro-processors, School of ComputerNational University of Defense TechnologyChangshaChina

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