Full-Space Programmable Metasurface for Controlling Both Reflected and Transmitted Waves Under the Same Polarization and in the Same Frequency Band.

Recently, there is a significant surge in the research and development of metasurfaces capable of controlling electromagnetic (EM) waves across full spatial space, and hence garner considerable attention. Numerous metasurfaces with diverse functions are meticulously designed and investigated in various studies. However, in such studies, the transmitted and reflected spaces are segregated by frequency or polarization, and some of them fail to achieve real-time control. To break the limitations, here, this study proposes a novel full-space programmable metasurface that can control the reflected and transmitted EM waves dynamically in the same polarization and frequency band. By designing a special reflection-transmission-type meta-atom loaded with five PIN diodes and switching the operational states of these diodes, it achieves independently adjustable reflected and transmitted phases. The transmissive and reflective pattern of the proposed metasurface can be controlled by field programmable gate array (FPGA). To demonstrate the robust EM manipulating capacities of the proposed full-space programmable metasurface, some essential functions are presented, such as beamforming and beam focusing, by fabricating a prototype with 16×8 meta-atoms. The proposed metasurface suggests wide-ranging potential in sensing and wireless communications.