HTS microstrip antenna array for circular polarization with cryostat

We report the comparison results of an HTS antenna array for circular polarization with a self cryostat and comparison with a gold counterpart. The HTS antenna array designed in this work was fabricated using a YBCO superconducting thin film on an MgO substrate, and the designed resonant frequency was 11.85 GHz. We used square patches with truncated corners for circular polarization and employed a corporate feed network using sequential rotation techniques for enhancement of axial ratio. A cryostat was constructed for the measurement of each antenna, and liquid nitrogen was used as a coolant. Measurements from HTS antennas, including return loss, bandwidth, gain, efficiency and axial ratio are presented and compared with those of gold counterparts. The measured results show that useful antennas can be made using the proposed architecture for satellite communication systems.