Active Holographic Metasurface for Electrically Controllable 2-D Beam Scanning

A two-dimensional (2-D) beam scanning holographic metasurface antenna is presented in this paper. Dynamic element varactor diodes are introduced into the metallic patch of metasurface elements, and the active metasurface is formed by the periodic arrangement of metasurface elements. This scheme enables a variable impedance distribution surface. The leaky radiation of the surface wave propagating on the metasurface is controlled by adjusting the voltage loaded on each active metasurface element, thus a programmable electrically controlled beam scanning is achieved. The proposed holographic metasurface is composed of 21 × 21 active metasurface elements. The radiation gain is stable within ±45° from the normal direction of the antenna plane, and the average simulated realized gain is 14.7 dBi. The proposed antenna has a great application prospect in modern communication scenarios due to its advantages of ultra-low profile, high gain, and excellent conformal characteristics.