Frequency-Selective Characteristics of Plasma-Energy Selective Surface Structure in High-Power Microwave Protection

This article proposes a novel dynamically tunable plasma-energy selective surface (Plasma-ESS) structure for protecting electronic and communication equipment from high-power microwave interference and damage. As a protective front-end, this structure utilizes the tunability of plasma to achieve efficient transmission and shielding effects for electromagnetic waves at different frequencies. Simulation results indicate that after passing through the Plasma-ESS structure, the electromagnetic waves exhibit minimal insertion loss (IL) at two frequency points, 5.52 and 16.71 GHz, with $S_{21}$ values of 0.414 and 0.336 dB, respectively. In addition, the electromagnetic waves demonstrate an IL of less than 2 dB across an ultrawideband frequency range of 14.01–18.51 GHz, providing efficient transmission performance and frequency selectivity for devices with wide operating bandwidths. Since plasma is a novel electromagnetic shielding material capable of selectively absorbing or reflecting electromagnetic waves, the influence of plasma parameters on electromagnetic wave transmission or shielding based on the Drude model is discussed. The results reveal that plasma at different frequencies can achieve dynamic frequency point shifts, offering theoretical guidance for high-power electromagnetic protection applications across various frequencies.