Time Domain Analysis of Electromagnetic Scattering from Multiple Cavities Embedded in a Ground Plane

Abstract

This work examines the scattered fields produced when a transient wave is reflected from an infinite PEC ground plane with multiple embedded cavities. Incident and reflected waves will be decomposed into TMz and TEz polarizations, with primary focus given to the TMz. Cavities may be unfilled, partially filled, or fully filled with non-magnetic dielectric material and no assumptions are made regarding similarity, regularity, or periodicity. The Newmark method is used to discretize time and a variational formulation is presented for each time step. The principle outcome is to show that the variational formulation of the scalar problem is well posed. Additionally, the variational formulation is applied in a stable numerical model using the FE-BI method. Interior fields are approximated using the FEM for each time step, then the boundary integral is applied using the appropriate Green's function to approximate exterior scattered fields. The exterior elds for one time step provide the boundary conditionsfor the interior problem at the next time step. In this way, the numerical model marches through time. Various numerical experiments are run to examine the effect of coupling on aperture and external fields. Of particular interest are the differences between single-cavity and multiple-cavity solutions.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Sep 15, 2016
Accession Number
AD1054265

Entities

People

  • Richard P. Uber

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms
  • Energy and Power Technologies
  • Sensors

DTIC Thesaurus Topics

  • Air Force
  • Computational Science
  • Dielectrics
  • Differential Equations
  • Electric Fields
  • Electromagnetic Fields
  • Electromagnetic Radiation
  • Electromagnetic Scattering
  • Equations
  • Geometry
  • Information Operations
  • Integrals
  • Magnetic Fields
  • Military Operations
  • Stealth Technology
  • Two Dimensional
  • United States

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)