The Journal of the Acoustical Society of Korea (한국음향학회지)

The Acoustical Society of Korea (한국음향학회)
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Measurement and simulation of high-frequency bistatic sea surface scattering channel in shallow water of Geoje bay

거제 내만해역에서의 고주파 양상태 해수면 음파산란 채널 측정 및 모의

  • 최강훈 (한양대학교 해양융합과학과) ;
  • 김용빈 (한양대학교 해양융합과학과) ;
  • 김시문 (선박해양플랜트연구소) ;
  • 최지웅 (한양대학교 ERICA 해양융합공학과)
  • Received : 2020.12.23
  • Accepted : 2021.01.05
  • Published : 2021.01.31
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Abstract

High-frequency bistatic sea surface scattering channels according to sea state were measured at an experimental site of Geoje bay in April 2020, and compared with predictions based on scattering theory. A linear frequency-modulated signal with a center frequency of 128 kHz and a bandwidth of 32 kHz was used for the acoustic measurements. Sea surface wavenumber spectrum was calculated from surface roughness data measured by a wave buoy, and bistatic scattering cross-section of Small Slope Approximation (SSA) based on the wavenumber spectrum was estimated. In addition, scattering from near-surface bubbles using wind speed measured during experiments was considered. Surface scattering channel intensity impulse responses were simulated using the scattering cross-section and the simulation results were compared and analyzed with the field data.

해수면 상태에 따른 고주파 양상태 해수면 음파산란 채널 측정 실험은 2020년 4월 거제 내만해역에서 수행되었으며 산란이론을 기반으로 한 모의결과와 비교하였다. 신호는 중심주파수 128 kHz, 대역폭 32 kHz의 선형 주파수 변조 신호를 이용하였다. 파고부이를 통해 측정된 해수면 거칠기로부터 해수면 파수 스펙트럼을 계산하였고 산란이론인 Small Slope Approximation(SSA)에 적용하여 해수면 거칠기에 의한 산란강도를 추정하였다. 또한 실험 당시 풍속을 이용하여 해수면 부근 공기방울층 음파산란을 고려하여 산란강도를 계산하였다. 모의된 산란강도를 이용하여 해수면 산란 채널 세기 임펄스 응답을 모의하였고, 해수면 파수 스펙트럼과 공기방울층 산란에 따른 모의결과를 측정치와 비교, 분석하였다.

Keywords

Acknowledgement

본 연구는 한국해양과학기술진흥원 국가R&D사업 "수중 광역 이동통신 시스템 기술개발(PMS4110)" 과제의 지원에 의해 수행되었습니다.

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