A Technique Combining the Path Calibration and Nonlinear Compensation in a Transmitting Antenna Array System

송신 배열 안테나의 경로 보정과 비선형 보상의 결합 기술

  • 임선민 (한국전자통신연구원) ;
  • 김민 (충남대학교 전자전파정보통신공학과) ;
  • 은창수 (충남대학교)
  • Received : 2012.03.23
  • Accepted : 2012.05.12
  • Published : 2012.05.25

Abstract

We propose a new scheme combining the calibration of the path imperfections and the compensation of HPA nonlinearity in the downlink OFDM smart antenna systems. We use a two term third-order polynomial (without second-order term) and the indirect learning architecture for calibration and compensation, to make each path of the antenna array have equal characteristics. We test our scheme with computer simulations. The result shows that, with the addition of only one third-order term, the adverse nonlinear effects as well as the those of linear imperfections can be effectively compensated.

본 논문에서는 스마트 안테나 시스템에 대해 경로 결함들의 보정과 전력 증폭기의 비선형성 보상을 결합하는 새로운 기술을 제안하였다. 배열 안테나의 각각의 경로들이 동일한 특성을 갖기 위한 보정과 보상을 위해 선형 항에 3차 항을 추가한 다항식과 간접 학습 구조를 사용하였다. 본 논문에서는 컴퓨터 모의실험을 통해 성능을 입증하였다. 모의실험 결과, 단 하나의 3차 항을 추가하여 선형 결함들뿐만 아니라 모든 비선형 효과까지 효율적으로 보상함을 확인하였다.

Keywords

References

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