Theory of Electromagnetic Shielding for Conducting Cylinders and Spheres

Abstract

The shielding of electromagnetic waves by cylindrical and spherical enclosures is analyzed. The electromagnetic shielding effectiveness is calculated as a function of frequency for a plane wave incident on hollow cylindrical and spherical conducting shells. The electromagnetic resonances for the cylinder and the sphere are investigated and the resonance conditions are derived for both structures. In addition, a simple asymptotic formula for the shielding effectiveness is developed which is a good approximation in the resonance regime. Numerical calculations are performed for both the cylinder and the sphere, and the shielding effectiveness is plotted as a function of frequency for a shield with an outer diameter of 155 mm, a thickness of 0.1mm, and a conductivity of 10 to the 7th per ohm per meter.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1991
Accession Number
ADA233261

Entities

People

  • John Podesta

Organizations

  • United States Army Armament Research, Development and Engineering Center

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Asymptotic Series
  • Cartesian Coordinates
  • Diffraction
  • Directed Energy Weapons
  • Electric Fields
  • Electromagnetic Fields
  • Electromagnetic Radiation
  • Electromagnetic Scattering
  • Electromagnetic Shielding
  • Electromagnetism
  • Frequency
  • Geometry
  • Magnetic Fields
  • Plane Waves
  • Resonant Frequency
  • Scattering
  • Wave Equations

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering