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

The Korean Institute of Commucations and Information Sciences (한국통신학회)
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Analysis of DFT-based Channel Estimation in OFDM System with Virtual Subcarriers

가상 부반송파가 존재하는 OFDM 시스템에서 DFT 기반 채널 추정 기법의 성능 분석

  • 곽경철 (연세대학교 전기전자공학과 정보통신연구실) ;
  • 홍대식 (연세대학교 전기전자공학과 정보통신연구실)
  • Published : 2008.10.30
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Abstract

In this paper, the effect of unobtainable channel frequency response (CFR) inside virtual subcarreiers on DFT-based channel estimation is derived and introduced numerically because the CFRs cause the leakage to the estimated channel and degrade the estimation performance. In addition, the performance of DFT-based channel estimation is analyzed with respect to the number of virtual subcarriers, pilot spacing and the number of unobtainable CFRs at equi-distance subcarriers inside virtual subcarriers.

가상 부반송파가 존재하는 orthogonal frequency division multiplex (OFDM)시스템에서 discrete Fourier transform (DFT) 기반 채널 추정은 가상 부반송파 내 부반송파에는 파일롯 부반송파를 배치할 수 없기 때문에 DFT-inverse DFT (IDFT)과정에서 채널 누수가 발생해서 원하는 채널 추정 성능을 얻을 수 없다. 본 논문에서는 가상 부반송파가 존재할 때 DFT 기반 채널 추정기법의 성능 분석을 통해 성능 열화 정도를 분석한다. 가상 부반송파의 수, 파일롯 부반송파의 간격, 가상 부반송파 내부의 배치 불가능한 파일롯 부반송파의 수에 따라 정의 된 채널 누수를 이용하여 분석한다.

Keywords

References

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