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

대한전자공학회 (The Institute of Electronics and Information Engineers)
권호 표지

MIMO OFDM 시스템을 위한 향상된 채널 추정 기법

An Enhaced Channel Estimation Technique for MIMO OFDM Systems

  • 신명철 (연세대학교 전기전자공학과) ;
  • 이학주 (연세대학교 전기전자공학과) ;
  • 심세준 (연세대학교 전기전자공학과) ;
  • 이충용 (연세대학교 전기전자공학과)
  • Shin Myeongcheol (Dept. of Electrical Electronic Engineering, Yonsei University) ;
  • Lee Hakju (Dept. of Electrical Electronic Engineering, Yonsei University) ;
  • Shim Seijoon (Dept. of Electrical Electronic Engineering, Yonsei University) ;
  • Lee Chungyong (Dept. of Electrical Electronic Engineering, Yonsei University)
  • 발행 : 2004.06.01
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⟨ 이전 논문 다음 논문 ⟩

초록

MIMO OFDM 시스템에서 comb형태의 훈련심볼을 사용하는 기존의 채널 추정방식은 가장자리 반송파 영역에서 채널 추정의 MSE(Mean Squared Error)가 큰 단점이 있다. 본 논문에서는 이러한 문제점을 해결하기 위해 순환구조를 갖는 comb형태 훈련심볼을 제안한다. 제안된 순환구조에서는 모든 종류의 comb 훈련심볼이 각 안테나로부터 순환 전송되며 수신 단에서는 각 comb 형태의 훈련심볼들을 이용해 채널을 추정한 후, MSE로부터 구해진 최적의 가중치를 곱함으로써 채널 주파수 응답을 추정한다 모의실험을 통해 제안된 방식이 기존의 comb 형태의 훈련심볼에 비해 높은 성능을 나타냄을 확인하였다.

In MIMO-OFDM systems, conventional channel estimation techniques using comb type training symbols give relatively large mean squared errors(MSEs) at the edge subcarriers. To reduce the MSEs at these subcarriers, a cyclic comb type training structure is proposed. In the proposed cyclic training structure, all types of training symbols are transmitted cyclically at each antenna. At the receiver, the channel frequency responses that are estimated using each training symbol are averaged with weights obtained from the corresponding MSEs. Computer simulations showed that the proposed cyclic training structure gives more SNR gain than the conventional training structure.

키워드

참고문헌

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