Broadband HTS microstrip antennas for satellite communication

The major limitation of high-T/sub c/ superconducting (HTS) microstrip antennas is the narrow bandwidth due to the high Q and thin substrate. Defining bandwidth as the frequency range over which standing wave ratio (SWR) 2:1 or less, HTS antenna bandwidths are typically 0.85% to 1.1%. Thus considerable effort has been focused on developing antennas for broadband operation. In this work the HTS antenna, which consists of two triangle-radiation patches, was designed and fabricated using a YBa/sub 2/Cu/sub 3/O/sub 7-x/ (YBCO) superconducting thin film on MgO substrate for broadband operation. The input impedance and other characteristics for this antenna have been calculated using the moment method. Experimental results for our HTS antenna were reported in terms of radiation patterns, return losses, bandwidths and other various characteristics. The bandwidth obtained was a significant 6.7%.