Dual-Frequency Co-Aperture Control of Beam Scanning by Programmable Metasurface

We propose a method to realize the programmable metasurface with control of beam scanning in the far field under dual frequencies. For the design of the unit cell, the dual-frequency radiated element located at the top layer is tailored, and the electrically reconfigurable microstrip phase shifter embedding with four varactors placed at the bottom layer can achieve the phase coverage of 360 degrees under the dual frequencies correspondingly. One unit cell is fabricated to verify the electromagnetic performances of radiation and reflection under dual frequencies in the standard waveguide. After that, the whole co-aperture metasurface composed of 128 unit cells is fabricated, and the radiated phase of each active unit cell is independently and continuously controlled by the voltage programmable system to realize the beam scanning in our experiment. Due to the measurement results, the high-quality beam can scan from −60° to 60° under the frequency of nearly 6 and 10 GHz, respectively, in the far field.