An Improved Method for Calculating Power Density in the Fresnel Region of of Circular Parabolic Reflector Antennas.

Abstract

A computer program is presented which calculates power density in the Fresnel region of circular parabolic reflector antennas. The aperture illumination model is the one-parameter circular distribution developed by Hansen. The program is applicable to the analysis of electrically large, center-fed (or Cassegrain) paraboloids with linearly polarized feeds. The scalar Kirchoff diffraction integral is solved numerically by Romberg integration for points both on and perpendicular to the antenna boresight. Axial results cannot be directly compared to any others obtained with this illumination model, but they are consistent with what is expected in the Fresnel region where a quadratic must be added to the linear phase term of the integral expression. Graphical results are presented for uniform illumination and for cases where the first sidelobe ratio is 20, 25, 30, and 35 dB.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1988
Accession Number
ADA190569

Entities

People

  • Johnnie E. Mize

Organizations

  • Air Force Institute of Technology

Tags

DTIC Thesaurus Topics

  • Antenna Radiation Patterns
  • Antennas
  • Computer Programs
  • Computers
  • Diffraction
  • Electrical Engineering
  • Electromagnetic Compatibility
  • Energy Transfer
  • Engineering
  • Far Field
  • Fresnel Zones
  • Near Field
  • Power Distribution
  • Radar
  • Radiation
  • Radiation Patterns
  • Reflectors

Fields of Study

  • Physics

Readers

  • Calculus or Mathematical Analysis
  • Fluid Dynamics.
  • Phased Array Antenna Design.