DocumentCode
773310
Title
Variable beamwidth reflector antenna by feed defocusing
Author
Olver, A.D. ; Syed, J.U.I.
Volume
142
Issue
5
fYear
1995
fDate
10/1/1995 12:00:00 AM
Firstpage
394
Abstract
The beamwidth of a reflector antenna may be varied by defocusing the feed. The radiation characteristics are studied for both axisymmetric and offset single reflector antennas using both geometric optics for understanding the operation and physical optics for a parametric study. The beamwidth may be increased by over 200% compared to the focused reflector before the main beam bifurcates, but the on-axis gain is reduced. Better performance is obtained with an offset reflector antenna. The study quantifies the limits of beam broadening which can be achieved. Measurements on a 30 GHz experimental antenna show good agreement with theory
Keywords
antenna radiation patterns; geometrical optics; offset reflector antennas; physical optics; reflector antenna feeds; 30 GHz; axisymmetric reflector antenna; feed defocusing; geometric optics; offset reflector antenna; on-axis gain; physical optics; radiation characteristics; variable beamwidth reflector antenna;
fLanguage
English
Journal_Title
Microwaves, Antennas and Propagation, IEE Proceedings
Publisher
iet
ISSN
1350-2417
Type
jour
DOI
10.1049/ip-map:19952082
Filename
487773
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