MetaShield: a Multi-Function AP-Surrounding Metasurface.

In this work, we present MetaShield, a multi-function configurable metasurface that is affixed to and surrounds an Access Point (AP). We design MetaShield with three core features: (i) it is composed of configurable meta-atoms with subwavelength-scale controllable electromagnetic (EM) response, (ii) it provides near-field coupling with fixed geometry between the metasurface and the AP's antennas, (iii) it is transmissive. With these features, we design two configurations for MetaShield to undertake two functions that can be realized simultaneously in different regions of the metasurface or sequentially as dictated by the AP's protocol stack: Angle-Selective Signal Enhancement and Directional Interference Mitigation. Over-the-air experiments at 150 GHz demonstrate over 8 dB signal enhancement and 15 dB interference suppression, while supporting 20 GHz bandwidth on a single surface.