Journal of the Institute of Electronics Engineers of Korea TC (대한전자공학회논문지TC)

The Institute of Electronics and Information Engineers (대한전자공학회)
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Novel Technique for Obtaining Diversity Gain Using Symbol Share In OFDM Systems

OFDM 시스템에서의 심볼 공유를 이용한 다이버시티 이득 획득 기법

  • Kang, Jae-Won (Department of Electrical and Electronic Engineering, Yonsei University) ;
  • Park, Jin-Bae (Department of Electrical and Electronic Engineering, Yonsei University) ;
  • Hwang, Hae-Gwang (Department of Electrical and Electronic Engineering, Yonsei University) ;
  • Kim, Kwang-Soon (Department of Electrical and Electronic Engineering, Yonsei University)
  • 강재원 (연세대학교 전기전자공학부) ;
  • 박진배 (연세대학교 전기전자공학부) ;
  • 황해 (연세대학교 전기전자공학부) ;
  • 김광순 (연세대학교 전기전자공학부)
  • Received : 2009.09.02
  • Accepted : 2010.12.10
  • Published : 2010.12.25
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Abstract

In this paper, the technique for obtaining diversity gain without increasing the antenna is proposed using symbol share in the OFDM systems. Proposed technique groups symbols which are mapped into different sub-carriers and these symbols are modulated by proposed constellation. Proposed constellation has the identical minimum distance with QPSK modulation constellation and obtain more frequency diversity gain. Also, proposed modulation scheme make it possible to increase data rate using subcarriers allocated symbols.

본 논문에서는 OFDM 시스템에서 추가적인 안테나 개수의 증가 없이 기존의 OFDM 시스템과 비교하였을 경우 보다 큰 다이버시티 이득을 획득함으로서 시스템 성능을 향상시키기 위한 기술을 제안한다. 제안된 기술은 주파수 선택적 채널에서 상이한 채널을 겪는 두 개의 부반송파를 그룹화해서 각 그룹의 부반송파에 할당되는 심볼을 공유한다. 제안된 변조 기법은 QPSK 기법과 동일한 심볼간 최소거리를 가지며 주파수 선택적 채널하에서 다이버시티 획득이 가능하도록 한다. 또한 제안된 성상도에 의해 발생하는 Null 심볼에 할당된 부반송파들을 유용하게 이용하여 데이터 전송 효율을 높일 수 있다.

Keywords

References

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