Journal of the Korea Institute of Information and Communication Engineering (한국정보통신학회논문지)

The Korea Institute of Information and Commucation Engineering (한국정보통신학회)
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Performance of M-ary QAM demapper with Max-Log-MAP

Max-Log-MAP 방식을 이용한 M-ary QAM Demapper의 성능

  • 이상근 (청강문화산업대학 이동통신과) ;
  • 이윤현 (한국항공대학교 전자 정보통신 컴퓨터공학부)
  • Published : 2006.01.01
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Abstract

In this paper, we present the performance of iterative decoding with a Turbo decoder and a M-ary QAM(Quadrature Amplitude Modulation) demapper. The demappers are designed with Max-Log-MAP algorithm and it's approximated one. In addition, we provide implementing block for the approximated algorithm. From the results of computer simulations, the approximated algorithm of the Max-Log-MAP has little bit worse than the Max-Log-MAP but suggests low complexity for practical implementation.

본 논문에서는 Max-Log-MAP 방식을 이용하여 M-ary QAM Demapper를 구성하고 이 출력을 터보 복호기에 입력시켜 반복 복호 결과를 보인다. Demapper는 일반적으로 널리 사용되는 Max-Log-MAP 방식과 이 방식의 구현 복잡도를 줄인 근사형 수식을 이용하고 실제 설계 방안도 제시한다. 컴퓨터 시뮬레이션 결과 Max-Log-MAP 방식에 비해 근사형 방식은 성능의 저하를 보이지만 설계 복잡도가 낮은 장점을 가지고 있다.

Keywords

References

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