DMT 시스템에서 반송파간 간섭제거에 대한 연구

A Study on the Inter-Carrier Interference Cancelation for DMT Systems

  • 정길수 (동양공업전문대학 전기전자통신공학부) ;
  • 이원석 (동양공업전문대학 전기전자통신공학부) ;
  • 강희훈 (여주대학 전자과)
  • Chung, Kil-Soo (School of Electrical Engineering, Dongyang Technical College) ;
  • Lee, Won-Seok (School of Electrical Engineering, Dongyang Technical College) ;
  • Kang, Hee-Hoon (Dept. of Electronics, Yeojoo Institute of Tech.)
  • 발행 : 2008.03.25

초록

DMT 변조 방식은 VDSL에 적용된 다중 반송파 변조 방식이다. DMT 변조 방식의 문제는 송수신 반송파 주파수들 사이의 주파수 오프셋(Offset)에 민감하다는 것이다. 이러한 주파수 오프셋은 DMT 심볼에서 반송파간 간섭을 야기한다. 본 논문에서는 칼만(Kalman) 필터링을 이용하여 ICI를 감소하는 방법을 제안한다. 제안한 방식은 다른 방식과의 성능과 대역폭 그리고 계산상 복잡도를 비교한다. 시뮬레이션 결과는 제안한 방식의 성능이 주파수 오프셋이 높은 경우와 높은 차수의 변조 방식에 대해서 다른 방식에 대해서 칼만 필터링을 이용한 방식이 더 좋은 성능을 나타내었다.

In this paper, Digital MultiTone(DMT) is an emerging multi-carrier modulation scheme, which has been adopted for VDSL(Very high speed Digital Subscribe Line). A problem of DMT is its sensitivity to frequency offset between the transmitted and received carrier frequencies. This frequency offset introduces inter-carrier interference(ICI) in the DMT symbol. This paper is proposed an ICI cancelation scheme using Kalman Filtering. The performance of the proposed method is compared with conventional methods in terms of bit error rate performance, bandwidth efficiency, and computational complexity. Through simulations, it is shown that for high values of the frequency offset and for higher order modulation schemes, the EKF(Enhanced Kalman Filtering) method perform better than the others.

키워드

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