Channel power control performance based on a focusing metasurface with MIM structure at 220-320 GHz

The high directivity of terahertz waves induces pronounced signal attenuation and scattering, particularly for cell-edge users. Metasurfaces offer a viable approach to reshape electromagnetic propagation. This paper proposes a reflective metasurface with a metal-insulator-metal (MIM) configuration, operating at 240 GHz with 60 GHz bandwidth, integrating 30^∘ anomalous reflection and beam focusing at 0.5 m. System-level experiments evaluate the reflective focusing performance and path loss within a metasurface-assisted wireless link, covering frequency (220-320 GHz), incidence angle (0^∘-15^∘), and reception distance (0.3-2 m). The results confirm pronounced focusing effects and low insertion loss, highlighting the potential of metasurfaces in alleviating weak signal reception at cell edges. Moreover, a dual-metasurface configuration reduces path loss below line-of-sight levels, demonstrating enhanced channel power control through collaborative metasurface deployment.