A normal mode model for estimating low-frequency acoustic transmission loss in the deep ocean.

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Author
Evans, Kirk Eden
Date
1975-09Advisor
Coppens, Alan B.
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This work describes a computer model (QMODE) which uses the normal mode method for the estimation of low-frequency long-range acoustic transmission loss in the deep ocean. Wentzel-Kramer-Brillouin (WKB) solutions for the phase speeds (eigenvalues) and modes (eigenfunctions). The WKB solutions are extended to consider the effects of the surface and bottom boundaries. The eigenvalues are initially estimated by a least-squares polynomial fit through sample results of the WKB characteristic equation. The effects of range dependence in the sound speed profile are simulated through the use of the adiabatic assumption, which has been extended to include the case of profiles with multiple sound channels. Results of the model agree generally with the transmission loss observed in two long-range acoustic experiments.
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This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.Collections
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