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A Superconducting Microwave Power Limiter for High-Performance Receiver Protection



James Booth, Kenneth Leong, Susan A. Schima


We report on the development of a microwave power limiter based on high-temperature superconductor technology. The power limiter takes the form of a 50 ohm coplanar waveguide transmission line that can be reversibly driven from the low-loss superconducting state into the high- loss normal state as microwave currents within the device exceed a critical value. This device has demonstrated very low insertion loss (<0.5 dB/cm at 70 K, 40 GHz) and extremely wide bandwidth (constant impedance up to 40 GHz) in the signal-pass state, with variable attenuation in the signal-block state. Switching times for transitions from the signal-pass state to the signal-block state are estimated to be on the order of a nanosecond or less. Reversible operation has been demonstrated for continuous-wave (CW) signals up to 10 W at 3 GHz, and for 100 's transient signals up to 100 W. This device should be valuable for protecting high-performance receiver components from high-power transients encountered in real-world applications.
Proceedings Title
Dig., IEEE Microwave Theory Tech. Intl. Symp.
Conference Dates
June 6-11, 2004
Conference Location
Fort Worth, TX, USA
Conference Title
IEEE MTT-S International Microwave Symposium


high temperature superconductor, microwave power limiter


Booth, J. , Leong, K. and Schima, S. (2004), A Superconducting Microwave Power Limiter for High-Performance Receiver Protection, Dig., IEEE Microwave Theory Tech. Intl. Symp., Fort Worth, TX, USA (Accessed February 29, 2024)
Created June 10, 2004, Updated October 12, 2021