On the determination of the phase center of gaussian horn antennas

Abstract

Gaussian horn antenna designs have experimentally demonstrated excellent performance to produce a very pure Gaussian beam mode with extremely low sidelobes and crosspolarization levels. These results make very attractive these antennas for high performance applications as satellite communications, radar and remote sensing. The particular position of the phase center inside the horn antenna is crucial in the subsequent process to design the mirror system to be illuminated by the antenna. The Gaussian horn antennas, because the feature to excite a Gaussian beam modes, have the phase center close to the horn throat instead of the output horn aperture as usual. This feature is particular of Gaussian horn antennas, and it supposes a change in the design process using these antennas. The mathematical determination, by correlation of the output fields with Gaussian structures, and the numerical demonstration, will be showed in this paper. Also, some considerations of the advantages or disadvantages of this property will be commented.