Electromagnetic Scattering from Two Dimensional Objects Using the Field Feedback Formulation

Abstract

Integral equations (IE's) are widely utilized to calculate induced currents on antennas and scatters, but they are seriously restricted in their ability to handle inhomogeneous penetrable structures having multiwavelength dimensions. The utilization of finite element (FE) techniques has not been as pervasive as the use of IE's. The IE representation matrix is 'full', containing few, if any, zero valued elements. The techniques for operating on these large- sized full matrices require undesirable amounts of processor time. FE techniques produce sparse matrices due to the strictly local interactions between discrete unknowns. The application of FE's to unbounded problems, however, requires supplementary enforcement of the far-field radiation conditions. The Field Feedback Formulation (FFF) circumvents the full-matrix computational 'bottleneck' by allowing FE based numerical methods to be employed. Even though the resultant spare matrices may be larger than the 'full' matrices discussed earlier, most elements have a value of zero. Numerical procedures exist to optimize operations with these sparse matrices. Calculational speeds can be orders of magnitude faster. Computer technique to implement and validate this new technique are the basic for this thesis. Excellent agreement with classical results are demonstrated. Theses.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1989
Accession Number
ADA209563

Entities

People

  • Thaddeus B. Welch Iii

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Boundary Value Problems
  • Cartesian Coordinates
  • Computational Fluid Dynamics
  • Computational Science
  • Computer Programming
  • Computer Programs
  • Computers
  • Contour Integrals
  • Differential Equations
  • Electromagnetic Scattering
  • Equations
  • Far Field
  • Integral Equations
  • Integrals
  • Radiation
  • Sparse Matrix
  • Two Dimensional

Readers

  • Calculus or Mathematical Analysis
  • Computational Modeling and Simulation
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering