THE BACKFIRE HELICAL ANTENNA.

Abstract

When the diameter of the ground plane of a conventional helical antenna is reduced to the diameter of the helix, different radiation characteristics are observed. That is, for a small ground plane feed, the helix radiates with its main beam in the backfire direction when the pitch angle is small. When the pitch angle is large, however, the backfire beam splits and scans towards broadside as the frequency is increased. A theoretical solution for the propagation constants of the fields along the helix is discussed, and the results are displayed in the form of k-beta diagrams. The results of impedance, pattern, and current distribution measurements are presented and interpreted in terms of this diagram. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jun 23, 1965
Accession Number
AD0626088

Entities

People

  • Tobe L. Sexson

Organizations

  • Sylvania Electric Products

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Antennas
  • Diameters
  • Frequency
  • Helical Antennas
  • Impedance
  • Measurement
  • Radiation

Fields of Study

  • Physics

Readers

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