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

The Korean Institute of Commucations and Information Sciences (한국통신학회)
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Improvements of the OFDM System Performance By Using the Characteristic of Circularly Polarized Waves and Carrier Interferometry Signals

원형편파특성과 반송파 간섭신호특성을 적용한 OFDM 시스템 성능 개선

  • 안재성 (부경대학교 정보통신공학과) ;
  • 하덕호 (부경대학교 전자컴퓨터정보통신공학부)
  • Published : 2007.08.31
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Abstract

In this paper, in order to enhance the performance improvements of both BER and PAPR characteristic for the conventional OFDM system, both circularly polarized waves and carrier interferometry signals which shows the robustic fading reduction effect are applied to the system, and then the performance of the proposed system has been evaluated by computer simulation. From the analysis, it can be seen that the system BER performance can be improved by 2 or 3 dB. Furthermore, it can be also seen that the PAPR characteristic can be markedly reduced.

OFDM(Orthogonal Frequency Division Multiplexing)신호는 독립적으로 변조된 다수의 부반송파들이 동위상으로 더해질 경우 신호의 크기가 크게 발생하여 PAPR(Peak-to-Average Power Ratio)이 크게 나타난다. PAPR이 커지면 시스템의 복잡도가 증가하고 RF 전력증폭기의 효율이 감소하므로 시스템의 성능 열화의 요인이 된다. 본 논문에서는, 기존의 OFDM 시스템의 BER 성능과 PAPR 특성을 개선하기위하여 페이딩 특성에 강인한 효과를 나타내는 원형편파와 반송파 간섭신호를 시스템에 함께 적용하여 컴퓨터 모의실험으로 그 성능을 평가하였다. 그 결과 시스템 BER 특성이 $2{\sim}3$[dB] 정도의 개선효과가 있었으며 PAPR특성도 크게 감소시킬 수 있음을 알 수가 있었다.

Keywords

References

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