Nonlinear Grounded Metasurfaces for Suppression of High-Power Pulsed RF Currents

High-power radio frequency transmitters can cause interference or damage to sensitive receivers and other electronic equipment. These signals may be coupled into circuitry through currents in the surfaces of metal enclosures, and even a small gap in conductive shielding can represent a vulnerable point of entry. This problem can be mitigated by using a lossy coating or a reactive surface to suppress surface currents. However, this may reduce the performance of other antenna systems or disturb other aspects of the electromagnetic design. Nonlinear metamaterials provide an attractive alternative. By including nonlinear behavior into a periodic structure through embedded electronic circuits, it is possible to construct a coating that provides minimal disturbance to low-power surface currents, but becomes strongly absorbing under high-power RF illumination. In this letter, a nonlinear metamaterial coating is introduced, and we demonstrate its performance as a thin, broadband, absorbing surface for high-power pulsed RF currents.