Accession Number : ADA192489

Title :   The Covariance of Scalar Fields Scattered by Pressure-Release Randomly Rough Surfaces.

Descriptive Note : Master's thesis,

Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK APPLIED RESEARCH LAB

Personal Author(s) : Restrepo, J M ; McDaniel, S T

PDF Url : ADA192489

Report Date : Dec 1987

Pagination or Media Count : 174

Abstract : Expressions for the spatial covariance of the scattered scalar field are presented. The scatterer is a randomly rough pressure-release surface with either Gaussian or Pierson-Stacy wavenumber spectrum. Three different models are presented: the Standard Model, which utilizes the Helmholtz-Kirchhoff integral as a starting point and uses an integration-by-parts technique to compute the random normal gradient; the Slope-Operator Model, developed using the Fresnel and Fraunhofer phase approximation, begins with a double-layer potential integral and relies on an operator to compute the dot product of the random normal gradient. Finally, the Composite-Roughness Model, which in essence merges perturbation techniques with the tangent plane formulations of the scattering integral is considered. Keywords: Acoustic fields, Acoustic scattering, Acoustic spectrum analysis, Acoustic wave coherence, Surface wave acoustic devices.

Descriptors :   *ACOUSTIC FIELDS, *ACOUSTIC SCATTERING, *SURFACE ACOUSTIC WAVE DEVICES, ACOUSTIC EQUIPMENT, ACOUSTIC WAVES, COHERENCE, COVARIANCE, FORMULATIONS, GRADIENTS, LAYERS, MODELS, PERTURBATIONS, SCALAR FUNCTIONS, SPATIAL DISTRIBUTION, SURFACE ROUGHNESS, TANGENTS, SPECTRUM ANALYSIS

Subject Categories : Acoustics
      Line, Surface and Bulk Acoustic Wave Devices

Distribution Statement : APPROVED FOR PUBLIC RELEASE