Design of an EBG Compact Low-Mass Antenna in C-band with dual circular polarisation

Global transmission communication systems from geostationary orbit require compact and light antennas to reduce as much as possible the overall mass of the on flight configuration. Within the frame of the ESA project Compact Low-Mass Global Antennas, EADS CASA Espacio and the Public University of Navarra are developing a light and compact C-band antenna with dual circular polarization. The design of the antenna is based on flat planar technology, leading to two different lines of work. The first one consists in a low profile patch array while the other is based on Electromagnetic Band Gap (EBG) superstrate technology. Both configurations are studied and traded-off for single band working modes in C-band at 3.7 GHz. They are evaluated in terms of compactness, mass and RF performance. The array layout and beam forming network implementation are detailed, as well as the radiator and EBG superstrate selection.