An EIT-Based Plasma-Integrated Metasurface for High-Power Microwave Protection

A novel topology based on electromagnetically induced transparency is introduced for high-power microwave protection. Two split ring resonators are placed side by side so the SRRs' gaps are mutually orthogonal. When a linearly polarized wave is incident to the unit cell, both resonators interact with the incident field so that a transparent window is introduced, providing a window for communication at low-power incident waves. Gas discharge tubes are implemented at the split gap region of the SRRs, which are transformed into plasma cells under high incident power, eliminating the transparent window and thus providing protection against high-power microwaves. The numerical and experimental results of a sample limiter are in complete agreement with an insertion loss of 0.4 dB at 3 GHz. In comparison, isolation goes as high as 30 dB at 100 W and increases with incident power. The power threshold can be tuned using DC biasing of plasma cells.