Characterization and Fabrication of Synthetic Rough Surfaces for Acoustical Scale-Model Experiments

Abstract

Diverse aspects of stochastic processes, time-series analysis and fractal geometry are applied to the problem of characterizing and fabricating scale-model representations of the ocean bottom for acoustical analysis. As these physical models of rough surfaces are of finite size and manufacturing resolution, they are properly treated as examples of band-limited fractional Brownian motion (FBM), a type of approximately self-affine fractal. A novel formalism for the generation and characterization of FBM surfaces is developed, and the high- and low-wave number bandwidth restrictions are described analytically and presented visually. Specific applications involving acoustic tank experiments for verifying the predictions of rough surface scattering theories are described. MATLAB code for creating and validating mathematical representations of FBM surfaces is provided.

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Document Details

Document Type
Technical Report
Publication Date
Aug 05, 2005
Accession Number
ADA452670

Entities

People

  • Jason E. Summers
  • Raymond J. Soukup
  • Robert F. Gragg

Organizations

  • United States Naval Research Laboratory

Tags

DTIC Thesaurus Topics

  • Acoustic Scattering
  • Acoustics
  • Computational Science
  • Computer-Aided Manufacturing
  • End Mill
  • Fabrication
  • Geometry
  • Manufacturing
  • Milling Machines
  • Order Statistics
  • Random Variables
  • Scattering
  • Seabed
  • Signal Processing
  • Stochastic Processes
  • Three Dimensional
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Computational Modeling and Simulation
  • Radar Systems Engineering.
  • Wave Propagation and Nonlinear Chaotic Dynamics.