Analysis of a Conformal Receiving Array of Slots in a Perfectly-Conducting Circular Cylinder by the Geometrical Theory of Diffraction.

Abstract

This report deals with an analysis of the voltages received by a conformal array of rectangular slots in a circular cylinder when it is illuminated by an electromagnetic plane wave. The received voltages are calculated via an admittance matrix formulation; this formulation requires a knowledge of the array admittance matrix whose elements contain the external aperture self and mutual admittances, respectively, and a matrix whose elements contain the short circuit modal currents induced in the slot apertures by the incoming plane wave. The induced short circuit currents and the external mutual admittances are very simply and accurately found via the geometrical theory of diffraction (GTD). Even though the GTD is a high frequency method, the GTD results employed herein are expected to be quite accurate for cylinders as small as three wavelengths in circumference. The analysis given in this report is based on the dominant mode approximation for the electric field in the slot apertures. Numerical results are presented for the voltages received by a three or four element slot array as a function of the angle of arrival (in azimuth) of the incoming plane wave. Axial, circumferential and inclined (45 deg) slot arrays are considered. It appears that such an array of slots in a cylinder can be effectively employed for the purposes of direction finding. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1975
Accession Number
ADA027506

Entities

People

  • P. H. Pathak

Organizations

  • Ohio State University

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Angle Of Arrival
  • Circuits
  • Diffraction
  • Direction Finding
  • Electric Fields
  • Frequency
  • Frequency Shift
  • Plane Waves
  • Short Circuits
  • Waves

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Phased Array Antenna Design.