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

The Korean Institute of Electromagnetic Engineering and Science (한국전자파학회)
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Demapping Algorithm for Applying the Multilevel Modulation Scheme to LDPC Decoding Based on DVB-S2

DVB-S2 기반 LDPC 복호기의 멀티레벨 변조 방식 적용을 위한 디맵핑 알고리즘

  • Jung Ji-Won (Department of Radio Science & Engineering, Korea Maritime University) ;
  • Jeong Jin-Hee (Department of Radio Science & Engineering, Korea Maritime University) ;
  • Kim Min-Hyuk (Department of Radio Science & Engineering, Korea Maritime University)
  • 정지원 (한국해양대학교 전파공학과) ;
  • 정진희 (한국해양대학교 전파공학과) ;
  • 김민혁 (한국해양대학교 전파공학과)
  • Published : 2006.07.01
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Abstract

DVB-S2 offers various coding rate and modulation schemes. Therefore this paper proposes bit split methods to applying to multilevel modulation. Log-likelihood ratio method splits multilevel symbols to soft decision symbols using the received in-phase and quadrature component based on Gaussian approximation. However it is too complicate to calculate and to implement hardware due to exponential and logarithm calculation. Therefore this paper presents Euclidean, MAX and Sector method to reduce the high complexity of LLR method.

DVB-S2 표준안에서는 다양한 부호화율과 그에 따른 다양한 변조 방식을 지원한다. 따라서 본 논문에서는 LDPC에 8 PSK 이상의 다치 변조 방식 적용을 위해 수신단에서 비트 분리 방법을 제시한다. 수신된 I, Q 심볼만을 이용하여 세 비트 이상의 비트를 분리하기 위한 LLR 방식에 기초를 하여 LLR 방식의 단점인 복잡도를 개선하기 위해 Euclidean, MAX, Sector 방식을 제시하였다.

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References

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