The Journal of Korean Institute of Communications and Information Sciences (한국통신학회논문지)

The Korean Institute of Commucations and Information Sciences (한국통신학회)
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Walsh Coded Training Signal Aided Time Domain Channel Estimation Scheme In MIMO-OFDM Systems

MIMO-OFDM 시스템에서 Walsh 부호화된 훈련 신호를 이용한 시간 영역 채널 추정 방식

  • 전형구 (동의대학교 정보통신공학과) ;
  • 장종욱 (동의대학교 컴퓨터공학과) ;
  • 송형규 (세종대학교 정보통신공학과)
  • Published : 2007.03.31
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Abstract

In this paper, we propose a novel Walsh coded training signal design and Walsh decoding method to estimate the channel response in MIMO-OFDM systems. The Walsh coded training signals are designed to have orthogonal property in time domain. Using the orthogonal property, the Walsh decoding process makes it possible to separate the desired training signal from the received signal and to estimate the channel response. The computer simulation results show that the proposed method exhibits almost the same performance as Li's original method using the optimal training sequence, even though the proposed method has much lower complexity.

본 논문에서는 MIMO-OFDM 시스템에서 월쉬 부호화된 훈련신호를 이용하는 새로운 채널 추정 방식을 제안하였다. 월쉬 부호화된 훈련신호는 시간 영역에서 서로 직교하도록 설계된다. 이러한 직교성을 이용하여 월쉬 디코딩을 수행하면 시간 영역에서 원하는 훈련 신호를 분리할 수 있고 채널 추정이 가능하다. 컴퓨터 시뮬레이션 결과 제안된 방법은 계산량 감소에도 불구하고 최적 훈련 신호를 사용하는Li의 원래 방법[4]과 비교했을 때 거의 동일한 mean square error (MSE) 성능을 보였다.

Keywords

References

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