The Journal of the Acoustical Society of Korea

The Acoustical Society of Korea (한국음향학회)
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Experimental Study of Backscattered Underwater Signals from Multiple Scatterers

다중 산란체에 의한 수중 산란신호 실험연구

  • Kim, Eunhye (Department of Earth ＆ Marine Sciences Hanyang University) ;
  • Yoon, Kwan-seob (Department of Earth ＆ Marine Sciences Hanyang University) ;
  • Jungyul Na (Department of Earth ＆ Marine Sciences Hanyang University)
  • Published : 2004.03.01
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Abstract

Backscattered underwater signals from multiple scatterers contain information regarding resolvable spatial distribution of scatterers. This experimental study describes the spectral characteristics of backscattered signal from multiple scatterers, which are regularly or randomly spaced, in terms of their amplitude and phase and a proper signal analysis that will eventually provide scatterer spacing estimation. Air-filled tubes suspended in water, steel balls and plastic tubes buried in the sediment are the multiple scatterers. The cepstrum and the spectral autocorrelation (SAC) methods were used to estimate the scatterer spacing from the backscattered signals. It was found that the SAC method could be improved by employing singular value decomposition (SVD) to extract the effective rank for the spectral components. Unlike the conventional method of estimating the density of scatterers within the insonified volume of water, this type of estimation method would provide better understanding of the spatial distribution of scatterers in the ocean.

Keywords

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