The Journal of the Acoustical Society of Korea (한국음향학회지)

The Acoustical Society of Korea (한국음향학회)
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A correction of synthetic aperture sonar image using the redundant phase center technique and phase gradient autofocus

Redundant phase center 기법과 phase gradient autofocus를 이용한 합성개구소나 영상 보정

  • 유정수 (울산대학교 조선해양공학부) ;
  • 백경민 (한국표준과학연구원 초음파표준팀)
  • Received : 2021.08.31
  • Accepted : 2021.10.07
  • Published : 2021.11.30
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Abstract

In the signal processing of synthetic aperture sonar, it is subject that the platform in which the sensor array is installed moves along the straight line path. In practical operation in underwater, however, the sensor platform will have trajectory disturbances, diverting from the line path. It causes phase errors in measured signals and then produces deteriorated SAS images. In this study, in order to develop towed SAS, as tools to remove the phase errors associated with the trajectory disturbances of the towfish, motion compensation technique using Redundant Phase Center (RPC) and also Phase Gradient Autofocus (PGA) method is investigated. The performances of these two approaches are examined by means of a simulation for SAS system having a sway disturbance.

수중 탐지를 위한 합성개구소나(Synthetic Aperture Sonar, SAS) 신호처리에서는 탑재플랫폼이 직선경로를 따라 주행한다고 가정한다. 그러나 실제로는 플랫폼의 복잡한 운동에 따른 궤적 교란으로 인해 SAS 영상에 번짐과 같은 왜곡이 발생한다. 본 연구에서는 예인형 SAS 개발을 위해 궤적 교란에 의한 SAS 영상 왜곡을 개선하기 위한 방법으로서, Redundant Phase Center (RPC)을 이용한 예인체 운동 추정 및 영상 보정, 그리고 자동 초점 기법인 Phase Gradient Autofocus (PGA) 기법에 대해 검토하였다. 그리고 시뮬레이션을 통해, sway로 인해 왜곡된 SAS 영상에 이 기법들을 적용하고 그 성능 및 유효성에 대해 살펴보았다.

Keywords

Acknowledgement

본 논문은 민군협력진흥원의 민군겸용기술과제인 "예인형 간섭계측합성개구소나(InSAS) 개발"(과제번호: 15-CM-SS-01)의 지원을 받아 수행된 연구 결과이다.

References

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