OFDM 시스템에서 주파수 오차와 위상 잡음에 의한 ICI를 제거하기 위한 효율적인 자가상쇄 기법

An Efficient ICI Self-Cancellation Method with Frequency Offset and Phase Noise in OPDM Systems

  • 박정환 (한국과학기술원 전자전산학과 통신신호처리 연구실) ;
  • 김형명 (한국과학기술원 전자전산학과 통신신호처리 연구실)
  • 발행 : 2009.02.28

초록

OFDM 시스템은 스펙트럼 효율 때문에 각광받고 있지만, ICI의 원인인 주파수 오차와 위상 잡음에 민감하다는 단점을 가지고 있다. ICI 자가상쇄 방법은 주파수 오차나 위상 잡음을 없애는데 좋은 성능을 가지고 있다. 이 논문에서는 N/2 간격의 conjugate 데이터 방법을 이용하여 주파수 오차와 위상잡음이 많이 존재하는 상황 (주파수 오차=$0.2{\sim}0.4$, 위상잡음=10도 정도)에서 성능이 좋은 ICI 자가 상쇄 방식을 제안한다. 또한, 파일럿을 이용하여 좀더 효율적인 ICI 자가상쇄 방법을 제안한다. 모의실험 결과는 이러한 제안된 방식의 성능이 기존의 방식보다 우수하다는 것을 확인할 수 있었다.

OFDM System is a promising transmission technique due to its spectral efficiency But, a major disadvantage of the OFDM system is its sensitivity to frequency offset and phase noise that makes intercarrier interference (ICI), which degrades the system performance severely The ICI self-cancellation method has a good performance with frequency offset or phase noise. This paper proposed the N/2 spacing data-conjugate method that works well in large frequency offset and phase noise (normalized frequency offset=0.2-0.4, phase noise standard deviation=about lodes). Also, an efficiency ICI cancellation method using pilot was proposed. Simulation results confirm that performance of the proposed scheme is better than conventional schemes.

키워드

참고문헌

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