Efficiency degradation caused by an axial feed defocusing in generalized classical axially-symmetric dual-reflector antennas

Author

Moreira, Fernando J S

Author_Institution

Dept. of Electron. Eng., Fed. Univ. of Minas Gerais, Belo Horizonte, Brazil

Volume

2

fYear

1999

fDate

1999

Firstpage

478

Abstract

The present work investigates the efficiency decay due to small axial feed displacements in classical axially-symmetric dual-reflector antennas. Analytical expressions for the antenna aperture field were previously derived from Geometrical Optics (GO) principles. These expressions enable the study of the aperture aberration dependence on small feed displacements and the consequent decrease in antenna efficiency. Parametric studies are conducted, in a generalized way, for the complete set of classical axially-symmetric dual-reflector antennas. Some representative geometries are further analyzed by the Moment Method (MM) to determine the accuracy of the present formulation

Keywords

antenna theory; axial symmetry; geometrical optics; method of moments; reflector antenna feeds; antenna aperture field; antenna efficiency; aperture aberration dependence; axial feed defocusing; axially-symmetric dual-reflector antennas; efficiency degradation; geometrical optics principles; moment method; small axial feed displacements; Antenna feeds; Aperture antennas; Degradation; Frequency; Geometrical optics; Geometry; Moment methods; Parametric study; Reflector antennas; Satellite antennas;

fLanguage

English

Publisher

ieee

Conference_Titel

Microwave and Optoelectronics Conference, 1999. SBMO/IEEE MTT-S, APS and LEOS - IMOC '99. International

Conference_Location

Rio de Janeiro

Print_ISBN

0-7803-5807-4

Type

conf

DOI

10.1109/IMOC.1999.866225

Filename

866225