Development of a Circularly Polarized Antenna Element with Hemispherical Coverage

Description

The purpose of the project is to develop a circularly polarized (CP) antenna element with hemispherical coverage. This project continues the work that had been done within the framework of the Danish Small Satellite Project on development of the antenna system for the RØMER satellite. The developed crossed-slot, cavity-backed antenna element serves as a baseline configuration for the current project.

Crossed-slot, cavity-backed antenna element for the RØMER satellite.

Two extensions to this antenna element, obtained by introducing one or more passive scattering structures, are investigated to define possible ways to improve the CP coverage and axial ratio in the upper hemisphere. The effect of the finite ground plane is taken into account, and the frequency range of primary interest is from 2.0GHz to 2.3GHz. The performances of the two extended antenna elements will be compared to each other and to that of the baseline configuration. The best candidate of the two antenna elements will be selected for the subsequent design and manufacturing.

Numerical investigations are carried out using Ørsted•DTU-developed software tool HOPES (Higher-Order Parallel Electromagnetic Simulator). HOPES is a full-wave 3D Method of Moment code based on recently developed higher-order hierarchical Legendre basis functions.

Also a further improvement will be done to the feed network for the RØMER satellite antenna. The design will be developed to mechanically integrate the feed network with the crossed-slot, cavity-backed antenna element.