High-power microwave limiter using a self-actuated plasma-based electromagnetically-induced-transparency topology

This paper presents an approach that uses a simple metamaterial topology that incorporates gas discharge tubes for high-power microwave protection. The design features two split-ring resonators positioned side by side with their splits oriented orthogonally. When exposed to low-power microwaves, each split-ring resonator induces a resonance that interacts to create a passband within a broad stop band that can be used for communication, facilitated by a phenomenon known as ``electromagnetically induced transparency'' (EIT). At high power levels, the gas in the integrated gas discharge tubes becomes ionized, forming plasma that acts as a switch to eliminate the EIT window, thereby reinstating the stop band for protection. Several prototypes have been developed for S-band operation based on this concept. There is good agreement among the analytical, numerical, and experimental results. The proposed device demonstrates superior protection with lower insertion loss in the off mode and higher isolation in the on mode. Its strong ability to handle high-power microwaves is achieved with the use of plasma-based switches instead of diodes, providing a reasonable response time and a straightforward design that enables rapid prototyping. In addition, the device demonstrates the ability to tune the frequency and power threshold, highlighting its versatility as a microwave protection device.