Advanced Models for Clutter

Abstract

This report summarizes three important results obtained during the reporting period. First, it is shown that the Luneberg-Kline asymptotic series for the current induced on a conducting rough surface always produces an error in the shadow zone. That is, the L-K series yields zero net current in the shadow zone for all terms in the asymptotic series. This shortcoming limits the usefulness of the L-K series for recovering diffraction effects. The method of smoothing is used to determine the fluctuating component of the field scattered by a randomly positioned collection of discrete scatterers to the level of the distorted wave Born approximation. Of particular importance here is the role of the coherent or average field in the medium as a source for the fluctuating field. Finally, it is shown how to go about developing an improved high frequency approximation for scattering from rough surfaces. In particular, it is shown that the shadowed Kirchhoff approximation should comprise the iterate in the basic integral equation for the current because it contains an infinite resummation of all of the shadowing effects.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1990
Accession Number
ADA232039

Entities

People

  • Gary Brown

Organizations

  • Virginia Tech

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Asymptotic Series
  • Born Approximations
  • Current Density
  • Diffraction
  • Electromagnetic Radiation
  • Electromagnetic Wave Propagation
  • Equations
  • Frequency
  • Geometry
  • Integral Equations
  • Integrals
  • Magnetic Fields
  • Mathematics
  • Scattering
  • Sequences
  • Statistics
  • Wave Propagation

Readers

  • Approximation Theory.
  • Radar Systems Engineering.
  • Wave Propagation and Nonlinear Chaotic Dynamics.