A Moment Solution for Electromagnetic Coupling through a Small Aperture.

Abstract

A three-term moment solution for electromagnetic coupling through a small aperture in a conducting screen is obtained. This solution gives the equivalent magnetic current in the aperture as a linear combination of the three quasi-static magnetic currents responsible for the three dipole fields seen in the far zone. Because only the dipole effects of the quasi-static currents are known, the elements of the excitation vector and the moment matrix can not be evaluated directly. Reciprocity is used to express the elements of the excitation vector in terms of the short-circuit incident fields. The imaginary parts of the elements of the moment matrix are evaluated by forcing the moment solution to be equal to the solution predicted by conventional small aperture theory. The real parts of the elements of the moment matrix are extracted from the quadratic expression for the power radiated by the magnetic current. The solution is applied to three examples - an aperture in a conducting plane, and aperture in a transverse wall between two rectangular waveguides, and an aperture in a lateral wall of a rectangular waveguide coupling to a half-space. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1981
Accession Number
ADA109721

Entities

People

  • Joseph R. Mautz
  • Roger F. Harrington

Organizations

  • Syracuse University

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Birds
  • Circuits
  • Classification
  • Coordinate Systems
  • Couplings
  • Electric Charge
  • Electric Conductors
  • Electric Current
  • Electric Fields
  • Electromagnetic Fields
  • Excitation
  • Far Field
  • Integral Equations
  • Magnetic Fields
  • Radiation
  • Short Circuits
  • Waveguides

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering

Technology Areas

  • Space
  • Space - Space Objects