Calculation of ring-shaped phase centers of feeds for ring-focus paraboloids

Author

Yang, Jian ; Kildal, Per-Simon

Author_Institution

Dept. of Electromagn., Chalmers Univ. of Technol., Goteborg, Sweden

Volume

48

Issue

4

fYear

2000

fDate

4/1/2000 12:00:00 AM

Firstpage

524

Lastpage

528

Abstract

Some primary feeds such as the hat feed radiate around the feed waveguide, which also acts as an axial support tube. Such feed antennas have phase centers in the form of rings rather than points. This paper presents a formula to calculate the location of the ring-shaped phase center. The optimum reflector is a ring-focus paraboloid with the ring focus coinciding with the ring-shaped phase center. The phase center formula is applied to two versions of the hat feed and it is shown that the aperture efficiencies can be improved by up to 0.5 dB when optimum ring-focus paraboloids are used instead of point-focus paraboloids

Keywords

reflector antenna feeds; aperture efficiencies; axial support tube; feed waveguide; hat feed; optimum reflector; optimum ring-focus paraboloids; phase center formula; phase centers; primary feeds; ring-focus paraboloid; ring-focus paraboloids; ring-shaped phase center; ring-shaped phase centers; Antenna feeds; Apertures; Electromagnetic waveguides; Frequency; Iterative methods; Lighting; Reflector antennas; Tellurium;

fLanguage

English

Journal_Title

Antennas and Propagation, IEEE Transactions on

Publisher

ieee

ISSN

0018-926X

Type

jour

DOI

10.1109/8.843665

Filename

843665