STUDY OF THE SCATTERING BEHAVIOR OF A SPHERE WITH AN ARBITRARILY PLACED CIRCUMFERENTIAL SLOT,

Abstract

The electromagnetic scattering behavior of a metallic sphere loaded with a circumferential slot arbitrarily placed with respect to the direction of incidence is studied. Under the assumption that the slot is of small but nonzero width with a constant electric field across it, the analysis for the external fields is exact. Expressions for the scattered far field components, as well as for the total surface field components, are derived and then used to investigate the extent to which the scattering behavior can be controlled by varying the loading admittances and the slot position. An explicit formula for the loading of the zeroth mode to annul the back scattering cross section is derived, and from this the desired loading is obtained by means of a lumped load at the center of a radial cavity backing the slot. In particular, emphasis is placed on the case where the slot is in the plane of incidence and normal to the direction of the incident electric vector. The numerical study is limited to the frequency range 0 < ka < 3.0, where a is the radius of the sphere, and results are presented primarily for back scattering. To verify some of these results, a comparison is made with experimental data obtained using a metallic sphere with an equatorial slot backed by a radial cavity of adjustable depth. (Author)

Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1967
Accession Number
AD0648717

Entities

People

  • Seichoong Chang
  • Thomas B. A. Senior

Organizations

  • University of Michigan

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Electric Fields
  • Electromagnetic Fields
  • Electromagnetic Radiation
  • Electromagnetic Scattering
  • Experimental Data
  • Far Field
  • Frequency
  • Scattering
  • Scattering Cross Sections

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering