Low-frequency broadband reflection attenuation via double layer plasma tube array

In this study, we developed a dual-layer parallel staggered plasma tube array to achieve strong −10 dB attenuation of low-frequency broadband electromagnetic waves. The periodic structure of the bilayer plasma array was fabricated using low-pressure glow discharge plasma tubes. Microwave anechoic chamber measurements demonstrated that the proposed staggered dual-layer configuration achieved broadband reflection attenuation in the 1–5.3 GHz range, thereby extending the effective attenuation bandwidth into the L-band at lower frequencies. Numerical simulations revealed that the broadband attenuation mechanism involved two distinct physical processes: resonance absorption by the intracolumnar plasma for high-frequency electromagnetic wave dissipation and localized surface plasmon resonance between adjacent plasma tubes for low-frequency electromagnetic energy absorption. In conclusion, our study proposes a novel strategy for designing plasma-based metamaterial absorbers with enhanced low-frequency broadband performance.