The Journal of the Acoustical Society of Korea (한국음향학회지)

The Acoustical Society of Korea (한국음향학회)
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Gram-Schmidt process based adaptive time-reversal processing

그람슈미트 과정 기반의 적응형 시역전 처리

  • 김동현 (한국해양대학교 수중운동체특화연구센터) ;
  • 변기훈 (한국해양대학교 해양과학기술융합학과) ;
  • 김재수 (한국해양대학교 해양공학과) ;
  • 신기철 (LIG넥스원(주) 해양연구소)
  • Received : 2023.12.06
  • Accepted : 2024.01.15
  • Published : 2024.03.31
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Abstract

Residual crosstalk has been considered as a major drawback of conventional time-reversal processing in the case of simultaneous multiple focusing. In this paper, the Gram-Schmidt process is applied to time-reversal processing to mitigate crosstalk in ocean waveguides for multiple probe sources. Experimental data-based numerical simulations confirm that nulls can be placed at multiple locations, and it is shown that different signals can be simultaneously focused at different probe source locations, ensuring distortionless responses in terms of active time-reversal processing. This focusing property is also shown to be much less affected by a reduction in the number of receivers than the adaptive time-reversal mirror method. The proposed method is shown to be effective in eliminating crosstalk in passive multi-input multi-output communications using sea-going data.

잔여의 채널 간 간섭은 일반적인 시역전 처리 기반의 동시 다중 집속에서의 주요 문제점으로 고려되어진다. 본 논문에서는, 다수의 음원이 존재하는 수중 도파관환경에서의 채널 간 간섭을 완화하기 위해 그람-슈미트 과정을 시역전 처리에 적용하였다. 해상 실험 데이터 기반 수치 시뮬레이션을 통해 여러 위치로의 널 형성 및 서로 다른 음원의 위치에서의 각기 다른 신호의 왜곡 없는 동시 다중 집속이 가능함을 능동 시역전 처리 관점에서 검증하였다. 또한, 적응 시역전 처리 방법에 비해 수신기 개수의 감소에 상대적으로 적은 영향을 받는 것을 확인하였다. 제안된 알고리즘을 통해 수동 다중 입·출력 수중 통신에서의 채널 간 간섭이 효율적으로 제거됨을 해상 실험 데이터를 통해 보였다.

Keywords

Acknowledgement

이 논문은 2023년도 정부(교육부)의 재원으로 한국연구재단의 지원을 받아 수행된 기초연구사업임(No. RS-2023-00271645). FAF05 및 SWellEx-96의 해양실험 자료를 사용할 수 있도록 허용해준 미국 스크립스 해양연구소(Scripps Institution of Oceanography, SIO)의 물리연구부(Marine Physical Lab., MPL)에 감사드립니다.

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