Examination on power handling capability of superconducting patch antenna

Measured results of power handling capability characteristics of superconducting patch antenna and it's improvement are reported. A direct-fed patch antenna is fabricated by YBa/sub 2/Cu/sub 3/O/sub y/ thin film with 50 nm thickness. The gain of the antenna does not change with the applied power up to 26.3 dBm at 12.3 K, but drop of the gain is observed more than 26.5 dBm. It is found by electromagnetic analysis that this gain drop occurs due to huge current concentration in the direct-fed patch. However, this current concentration can be reduced using the gap-coupled feed, and breakdown power is expected to be three times larger than that of direct feed.