Modification of Parabolic Dish Antenna Pattern Using Two Symmetrically Placed Circular Flat Plates.

Abstract

This study aims to formulate a method of predicting the far field pattern of a parabolic dish antenna with two moveable flat plates mounted symmetrically on either side of the feed horn. The approach taken has been to first analyze the radiation pattern of the antenna with the disks at certain heights out from the surface of the dish. To do this the near-field radiation in amplitude and phase was measured over a plane surface in the near-field and the values were then transformed into the far field using a Fast Fourier Transform. Far field pattern values of the antenna were directly measured for each setting of the plates. The results obtained from the Fast Fourier Transform of the near field data were in good agreement with the values obtained by measurement. Finally, an approximate model of the antenna was developed and implemented as a computer program. This model, while relatively unsophisticated, provided some insights into the changes in the near field phase distribution caused by the moveable circular flat plates.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1987
Accession Number
ADA189543

Entities

People

  • Glen C. Thorpe

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Abstracts
  • Accuracy
  • Air Force
  • Antenna Radiation Patterns
  • Antennas
  • Computer Programs
  • Computers
  • Engineering
  • Far Field
  • Fast Fourier Transforms
  • Materials
  • Near Field
  • Radiation Patterns
  • Reflectors
  • Schools
  • Three Dimensional
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Oncology