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Performance Improvement of the Smart Antenna Placed in Wi-Fi Access Point

와이파이AP 용 FFT 전단 스마트안테나의 성능 개선

  • Hong, Young-Jin (Department of Electrical Engineering, Tongmyong University)
  • 홍영진 (동명대학교 전기공학과)
  • Received : 2013.04.16
  • Accepted : 2013.05.09
  • Published : 2013.05.31

Abstract

OFDM Wi-Fi AP is susceptible to the co-channel interference. As a countermeasure, the insertion of a smart has been addressed. Despite of the guaranteed efficiency, the complexity of the post-FFT algorithm often keeps itself from being selected as the countermeasure. Instead, simply constructed pre-FFT smart antenna of which the algorithm is based on the received signal covariance matrix is commonly used and the mathematical modeling of it has been deployed. Computer simulations evaluating the improved BER characteristics of the proposed pre-FFT using the covariance matrix of channel estimator output have been carried out. It has been demonstrated that channel matrix output based smart antenna is superior to that using received signal covariance matrix.

Keywords

Covariance;Multipath;OFDM;Pre-FFT;Weight vector

Acknowledgement

Supported by : 동명대학교

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