The Journal of the Acoustical Society of Korea (한국음향학회지)

The Acoustical Society of Korea (한국음향학회)
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Low-Frequency Normal Mode Reverberation Model

저주파수 정상모드 잔향음 모델

  • 오선택 (한국해양과학기술원 해양방위연구센터) ;
  • 조성호 (한국해양과학기술원 해양방위연구센터) ;
  • 강돈혁 (한국해양과학기술원 해양방위연구센터) ;
  • 박경주 (해군사관학교)
  • Received : 2015.03.17
  • Accepted : 2015.04.16
  • Published : 2015.05.31
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Abstract

In this paper, a normal mode reverberation model for a range-independent environment of shallow water is proposed to calculate the reverberation level in the low-frequency range. Normal mode is used to calculate the acoustic energy propagating from the source to the scattering area and from the scattering area to the receiver. Each mode is decomposed into up and down going waves to consider scattering strength at the scattering area. The scattering functional form combines Lambert's law with a Gaussian-like term near the specular direction based on Kirchhoff approximation considering bottom condition. For verification of the suggested model, the result is relatively compared to several solutions of the problem XI and XV in the Reverberation Modeling Workshop I sponsored by the US Office of Naval Research.

본 논문에서는 천해의 거리 독립환경에서 저주파수 대역의 잔향음 준위를 계산하는 정상모드 잔향음 모델 개발을 제안하였다. 정상모드를 이용하여 음원에서 산란체, 산란체에서 수신기까지의 음파 전달을 계산하였다. 산란 면적에서 상하로 전달되는 음파는 각 모드를 이용하여 고려하였다. 산란함수는 기존에 제시된 해저면 조건을 고려한 람베르트 공식(Lambert's law)과 반사각 부근에서는 Kirchhoff 근사법에 의한 가우시안 형태를 조합하였다. 제안 모델을 검증하기 위해 미국 ONR(Office of Naval Research)이 지원한 제 I회 잔향음 모델링 워크샵(Reverberation Modeling Workshop I, RMW I)의 XI, XV번 문제를 기준으로 상대비교를 수행하였다.

Keywords

References

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