한국통신학회논문지 (The Journal of Korean Institute of Communications and Information Sciences)

한국통신학회 (The Korean Institute of Commucations and Information Sciences)
권호 표지

저전력 및 면적 효율적인 터보 복호기를 위한 정규화 유닛 설계

Design of the Normalization Unit for a Low-Power and Area-Efficient Turbo Decoders

  • 문제우 (서강대학교 전자공학과 CAD & Computer System 연구실) ;
  • 김식 (서강대학교 전자공학과 CAD & Computer System 연구실) ;
  • 황선영 (서강대학교 전자공학과 CAD & Computer System 연구실)
  • 발행 : 2003.11.01
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초록

본 논문은 블록 MAP 터보 복호기의 상태 메트릭 계산 유닛을 위한 정규화 방식을 제안한다. 제안된 방식은 정규화를 위해 격자단(trellis stage)에서 하나의 상태 메트릭 값을 모든 상태 메트릭에 빼주고 쉬프트 시키는 구조를 갖게 되어, 상태 메트릭 계산이 많은 블록 MAP 복호기의 격자단에서 하나의 상태 메트릭을 줄여 파워 소모와 메모리 요구량을 줄일 수 있다. 시뮬레이션 결과 제안된 정규화 구조를 적용한 터보 복호기는 기존의 블록 MAP 터보 복호기에 비해 동적 파워 소모는 17.9%까지 감소하고 면적은 6.6%까지 감소함을 확인하였다.

This paper proposes a novel normalization scheme in the state metric calculation unit for the Block-wise MAP Turbo decoder. The proposed scheme subtracts one of four metrics from the state metrics in a trellis stage and shifts, if necessary, those metrics for normalization. The proposed architecture can reduce power consumption and memory requirement by reducing the number of the state metrics by one in a trellis stage in the Block-wise MAP decoder which requires an intensive state metric calculations. Simulation results show that dynamic power has been reduced by 17.9% and area has been reduced by 6.6% in the Turbo decoder employing the proposed normalization scheme, when compared to the conventional Block-wise MAP Turbo decoders.

키워드

참고문헌

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