한국전자파학회논문지 (The Journal of Korean Institute of Electromagnetic Engineering and Science)

  • 제22권10호
  • /
  • Pages.1020-1023
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  • 2011
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  • 1226-3133(pISSN)
  • /
  • 2288-226X(eISSN)
한국전자파학회 (The Korean Institute of Electromagnetic Engineering and Science)
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반복등화를 위한 LLR 연판정 비트 정보를 이용한 M-QAM 심벌 Remapping

M-QAM Symbol Remapping Using LLR Soft Bit Information for Iterative Equalization

  • 김근배 (한양대학교 전자통신컴퓨터공학과) ;
  • 박상규 (한양대학교 전자통신컴퓨터공학과)
  • Kim, Geun-Bae (Department of Electronics and Computer Engineering, Hanyang University) ;
  • Park, Sang-Kyu (Department of Electronics and Computer Engineering, Hanyang University)
  • 발행 : 2011.10.31
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초록

본 논문에서는 반복 복호 후 얻게 되는 LLR(Log Likelihood Ratio)로 표현되는 연판정 비트 정보를 이용하여 송신된 BRGC(Binary Reflected Gray Code) M-QAM(M-ary Quadrature Amplitude Modulation) 신호 심벌을 remapping하는 방법을 제시한다. Remapping하기 위해서는 지수함수(exponential function)연산이나 하이퍼블릭 탄젠트(tanh) 함수를 이용하여야 한다. BRGC의 맵핑 법칙에 의해 심벌 remapping은 재귀(recursive) 연산을 이용한다. 또한, 구현 복잡도를 줄이기 위하여 curve fitting 방식을 제안한다.

In this paper, we present a symbol remapping method of BRGC M-ary QAM signal by using LLR soft bit decision information which is obtained after iterative decoding process. In order to reconstruct estimated transmitted signal constellation, we have to use exponential or hyperbolic tangent(tanh) function resulting in high implementation complexity. The BRGC mapping rule enables us to use a recursive operation. In addtion, we reduce the implementing complexity by using a curve fitting algorithm.

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참고문헌

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