Title :
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
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;
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
DOI :
10.1109/IMOC.1999.866225
