A Backscattering-Enhanced Metasurface with Dual-Polarization Under Large-Angle Oblique Incidence

The flexible control of electromagnetic waves by metasurfaces has gained significant attention. However, there is limited research on planar metasurfaces for backscattering enhancement in the microwave frequency band. One challenge arises when the incident wave angle becomes too large, as it becomes difficult to accurately reflect the waves at the desired angle. In this paper, a planar phase gradient metasurface is designed. The reflective unit cell can cover a huge phase variation of at least 332° when the incident angle of electromagnetic waves is 60° and the frequency is 10GHz. Simulation tests were conducted using the metasurface with thirteen different unit cells arrangements. The results demonstrate that both TM polarized and TE polarized waves can be effectively reflected backwards at an oblique incidence angle of 60°. The strongest backscattering angle are found to be 59° and 58° respectively, achieving backscattering enhancement in consistent with the expected angle.