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Improved Max-Log-MAP Turbo Decoding by Extrinsic Information Scaling and Combining

  • Lei Sun
  • Hua WangEmail author
Conference paper
Part of the Lecture Notes in Electrical Engineering book series (LNEE, volume 516)

Abstract

Turbo codes are among the best error-correcting codes, but trade-offs between performance and complexity in decoding are required for hardware implementation. In this paper, a novel extrinsic information scaling scheme for max-log-MAP decoder is proposed. It scales and combines extrinsic information generated at successive iteration round. The proposed method is evaluated for 3GPP LTE turbo codes in terms of decoding performance, complexity, and convergence. The simulation results show it has decoding gain near to log-MAP while keeps almost the same computation complexity as max-log-MAP with slight increment in memory resource. Moreover, it maintains insensitivity to SNR estimation error of max-log-MAP algorithm. Compared with conventional scaling scheme, it accelerates extrinsic information exchange between two constituent decoders to get better convergence and decoding performance.

Keywords

Turbo codes Extrinsic information Scaling factor 

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Copyright information

© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  1. 1.School of Information and ElectronicsBeijing Institute of TechnologyBeijingChina

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