Stochastic Modelling of EM Scattering from Foliage

Abstract

This project focused on the development and evaluation of analytical methods for the description of scattering and absorption of electromagnetic radiation by dense foliage. The key consideration has been the description of multiple scattering processes in a random medium. Three different techniques for the description of microscopic scattering processes are discussed in this report. The T-matrix approach to multiple scattering represents the field at an individual scattering center in terms of an equivalent field produced by the other scatterers. It supports several natural approximations for this equivalent field which take multiple scattering processes into account at various levels of detail. The Coherent Potential Approximation is developed in detail. The homogenization method is a technique for the derivation of an equivalent representation of the scattering process in terms of an asymptotic analysis of Maxwell's equations in the limit as the separation between the scattering centers approaches zero. Bounds for the effective parameter representations are also discussed. Scattering from foliage covered terrain on a macroscopic scale is treated by using the approximations to develop effective media representations of the foliage. These are used in combination with an analytical methodology based on the method of smoothing perturbation to treat the foliage as an interface region with a very rough boundary. Keywords: Radar scattering; Radar clutter. (JHD)

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1989
Accession Number
ADA213118

Entities

People

  • Gilmore L. Blankenship

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Asymptotic Series
  • Boundary Value Problems
  • Complex Variables
  • Composite Materials
  • Computational Science
  • Dielectric Permittivity
  • Differential Equations
  • Electromagnetic Radiation
  • Equations
  • Frequency
  • Geometry
  • Grazing Angles
  • Partial Differential Equations
  • Radiation
  • Random Variables
  • Variational Principles
  • Wave Equations

Readers

  • Calculus or Mathematical Analysis
  • Plasma Physics / Magnetohydrodynamics
  • Radar Systems Engineering.