Journal of the Institute of Electronics and Information Engineers (전자공학회논문지)

The Institute of Electronics and Information Engineers (대한전자공학회)
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A Study on Autofocus Method for Back-Projection Algorithm under the Squint Mode in Synthetic Aperture Radar

스퀸트 모드 SAR 영상 형성을 위한 역투영 알고리즘에서의 자동초점 기법 적용 연구

  • Hwang, Jeonghun (Department of Electronics Engineering Chungnam National University) ;
  • Kim, Whan-Woo (Department of Electronics Engineering Chungnam National University)
  • Received : 2017.02.17
  • Accepted : 2017.06.12
  • Published : 2017.07.25
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Abstract

Autofocus(AF) Method is essential to overcome the performance degradation due to motion measurement errors under airborne SAR environment. In this paper, back-projection algorithm(BPA) is applied to SAR raw data acquired under the squinted mode, and preprocessing algorithm of AF for BPA is investigated. To apply AF to SAR image effectively, image backplane rotation method and doppler location alignment function for BPA are proposed. The proposed method is applied to SAR raw data acquired in a flight test and shows excellent performance improvement in real data.

요동이 존재하는 환경에서, 요동 측정 오차에 의한 성능 저하를 극복하기 위한 신호처리 방식의 자동초점(Autofocus, AF) 기법의 적용은 필수적이다. 본 논문에서는 스퀸트 모드에서 획득한 합성 개구면 레이다 데이터에 역투영 알고리즘(back-projection algorithm, BPA)으로 영상을 형성하고, AF를 효과적으로 적용하기 위한 방식을 연구하였다. 자동 초점 기법의 효과적인 적용을 위해 BPA 영상을 회전한 상태로 형성하는 방식을 제안하며, 이때 필요한 후처리 도플러 위치 정렬 함수를 유도하였으며, 비행시험을 통해 획득한 SAR(Synthetic Aperture Radar, SAR) 원시 데이터에 적용하여 성능 개선을 확인함으로써, 실 데이터에서도 유효한 방식임을 확인하였다.

Keywords

References

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