Design of Electromagnetic Transparent Antennas Based on Drude Metasurface for High-Band Compatibility

With the increase of system complexity in wireless communications, higher requirements on miniaturization and integration are put forward for future antennas. Antennas of different frequency bands need to be placed together to achieve multiple communication goals. However, when a large-sized antenna operating at a low-band (LB) is used alongside a small-sized antenna operating at a high-band (HB), the radiation from the former can block the latter, thereby impacting the overall functioning of the antenna system. In this work, we propose a novel method for designing electromagnetic (EM) transparent antennas based on Drude metasurfaces. A dipole antenna made of Drude metasurfaces can maintain the radiation pattern of nearby HB antenna without compromising on radiation performance compared to the conventional metal-based one. An interconnected metasurface is designed to ensure low surface conductivity at HB yet high surface conductivity at LB, thus providing low radar cross section (RCS) compatible with the HB antennas. A prototype of the EM transparent dipole antenna is experimentally demonstrated and microwave measurements verify its capabilities in strong radiation and suppressing scattering at the LB and HB, respectively. Our results demonstrate an alternative way of solving EM blockages in multiband antenna systems by replacing conventional antennas with Drude-type meta-antennas.