Digital Coding EM Metasurface to Reconfigurable the Radiation Beam Controlled by Light

this manuscript presents the digital coding metasurface control by light in remote mode to dynamically manipulate the EM (electromagnetic wave) in real-time. The varactor diode is embedded in the digital metasurface that changes the EM characteristics of the metasurface without altering its physical dimensions. The photodiode and voltage-driven module are connected to control the varactor diode loaded in the unit cell element, reducing the system's overall volume and cross-talk between the D.C. signal and EM wave. The photodiode module converts the illuminating light intensity into voltage and tunes the unit cell's states in a non-contact way. These arrangements of digital coding Meta surface can manipulate the EM wave after applying the different coding sequences and generate beam splitting and deflection of the radiation pattern. The proposed digital coding Meta surface is 1-bit coding composed of "0" and "1" unit cell elements corresponding to 0 and 180-degree phase responses respectively. The design and simulation of the proposed unit cell element and digitally coded large array are carried out and observed the amplitude, phase response and beam splitting characteristics which may find promising applications in wireless communication, RCS Reduction, and OAM beam generation.