A Tunable Coded Metasurface for Controlling Reflection Amplitude and Phase in the X-Band

In this paper, a tunable coded metasurface designed to control reflection amplitude and phase in the X-band is introduced. The structure comprises a slotted dual-ring metal structure, a dielectric substrate, foam support material, and a metal backplane. Switching characteristics are realized through PIN diodes, with the biasing network seamlessly integrated into the structure. Simulation results show that the metasurface achieves complete reflection in both ON and OFF states of the PIN diodes, maintaining a phase difference of
$180^{\circ}\pm 27^{\circ}$
within the frequency range of 7.1-10.3 GHz. Operating the PIN diodes in the nonlinear region reveals a dynamic absorption range of approximately 30 dB. The research outcomes suggest potential applications in electromagnetic stealth technology, beamforming control, and other relevant fields.