A Numerical Method for Solving for Normal Modes with Impedance Bottom

Abstract

This thesis describes the development of a computer program that calculates the propagation loss for low frequencies in a shallow ocean given the depth of source and receiver, the sound speed profile of the water, the frequency of the source, and the impedance and sound speed in the bottom. The program does this by computing the sum of normal modes for a specified set of boundary conditions. At the surface, perfect pressure release is assumed, and the boundary condition at the bottom is one of impedance mismatch An effort was made to predict develop a Fast Field Program, which would use a FFT to predict propagation loss at a variety of ranges by solving a discrete set of wave numbers, but development was not completed. Keywords include: Normal modes; Fast field program; Impedance bottom; and Propagation loss.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1986
Accession Number
ADA176591

Entities

People

  • Douglas Cantley

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Advanced Electronics

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  • Absorption
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  • Difference Equations
  • Differential Equations
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  • Wave Equations

Fields of Study

  • Physics

Readers

  • Acoustical Oceanography.
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Microwave Engineering.