Journal of the Institute of Electronics Engineers of Korea TC (대한전자공학회논문지TC)

The Institute of Electronics and Information Engineers (대한전자공학회)
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Performance Analysis of OFDMA Uplink Systems with Symbol Timing Misalignment

사용자간 상대적인 시간오차에 의한 OFDMA 역방향 시스템의 성능 분석

  • Park Myonghee (Dept. of Electrical and Electronic Eng., Yonsei University) ;
  • Hong Daesik (Dept. of Electrical and Electronic Eng., Yonsei University)
  • 박명희 (연세대학교 전기전자공학과) ;
  • 홍대식 (연세대학교 전기전자공학과)
  • Published : 2005.02.01
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Abstract

This paper presents our investigation for the effect of symbol timing errors in orthogonal frequency division multiple access (OFDMA) uplink systems. We express the symbol timing errors between users as the symbol timing misalignments with respect to the desired user. Then, we derive an explicit expression of the average effective signal-to-interference-plus-noise ratio. (SINR) as a function of the maximum value of the symbol timing misalignments. Based on the resulting SINR degradation, we evaluate the SINR gain with guard subcarriers in order to mitigate the effect of the symbol timing misalignments.

본 논문에서는 OFDMA 역방향 시스템에서 시간오차에 의한 사용자간 간섭을 분석하고 역방향 수신기의 성능 열화 정도를 제시한다. 이를 위해, 각 사용자의 서로 다른 시간오차를 기준 사용자 대한 상대적인 시간오차로 표현한다. 그리고 역방향 수신기의 평균 신호대 간섭잡음비를 상대적인 시간오차의 최대값을 변수로 갖는 함수로 유도한다. 분석결과는 상대적인 시간오차 증가에 의한 평균 신호대 간섭잡음비의 성능 열화로 확인하였다. 또한, 데이터 부반송파 사이의 보호 부반송파를 사용하여 상대적인 시간오차에 의한 사용자간 간섭의 영향을 감소시킬 수 있음을 확인하였다.

Keywords

References

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