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

The Institute of Electronics and Information Engineers (대한전자공학회)
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Frequency Offset Estimation Performance Analysis in OFDM Packet Communication Systems with Unequal Gain Allocation of Training Sequences

OFDM 무선 패킷 통신 시스템에서의 비균일 훈련 심볼 이득 할당에 의한 주파수 오프셋 예측 성능 분석

  • Kwak, Jae-Min (SoC Research Center, Korea Electronics Technology Institute)
  • 곽재민 (전자부품연구원 SoC연구센터)
  • Published : 2007.10.25
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Abstract

In this paper, we proposed an frequency offset estimation scheme which can be used for packet based OFDM communication systems such as IEEE802.11a and IEEE802.11p physical layer. Proposed estimation scheme can adjust the gain allocation ratio between long training symbol and short training symbol while maintaining average power of overall training sequence so that we can obtain the reference parameters for MSE performance improvement. The preamble structure considered in this paper is based on the preamble specified in IEEE802.11a and IEEE802.11p standardization group. From the simulation results, it is shown that power ratio between long training symbol and short training symbol must vanes for achieving lower frequency offset estimation error as channel SNR condition is changed. Also it is known oat proposed scheme can achieve better performance than conventional one.

본 논문에서는 IEEE802.11a나 IEEE802.11p의 물리계층과 같은 패킷기반의 OFDM 통신 시스템에 적용할 수 있는 주파수 오프셋 예측기법을 제안하고 성능을 분석하여 기준기법과 비교하였다. 제안 기법에서는 긴 훈련심볼과 짧은 훈련심볼에 할당되는 이득을 전체적으로 일정하게 유지하면서도 이득 할당비를 조절할 수 있도록 하여 채널 상황에 따라 주파수 오프셋 에러에 대한 MSE 성능을 향상시키기 위한 이득 할당비를 알아낼 수 있다. 본 논문에서 고려한 훈련심볼은 IEEE802.11a와 IEEE802.11p의 표준화 그룹에서 적용된 프리앰블을 적용하였다. 시뮬레이션 결과에 의해, 채널 SNR 상황에 따라 주파수 오프셋 에러를 최소화하기 위한 긴 훈련심볼 대 짧은 훈련심볼의 전력비가 다르며, 제안한 기법에 의한 주파수 오프셋 에러에 대한 MSE 성능이 기존의 기법보다 우수함을 확인하였다.

Keywords

References

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