Wide-Angle Broadband Cancellation of Scattering from Metasurfaces with OAM and Combined Phase Profiles

The mechanisms of wide-angle broadband phase scattering cancellation from Patcharatnam-Berry (PB) metasurfaces (MSs) with orbital angular momentum (OAM) and combined phase profiles are examined. MS modules (structural elements) consisting of 144 meta-particles in the form of rectangular patches with rectangular cutouts are designed. The scattering characteristics of MS modules of the same size, differing in different PB-phase profiles, are compared: a module with OAM generation, modules with two different parabolic profiles (concave and convex), and modules with a combination of an OAM profile and a parabolic profile. The simulation showed that all profiles provide 8–10 dB cancellation of backscattered co- and cross-fields in the 8.5–21 GHz band. Parabolic profiles produce vortex scattering with greater diffusion. Combining these profiles with the OAM profile demonstrates the greatest diffusion, with the generation of two coaxial central vortices with different opening angles and OAM modes. Wide-angle diffuse co-field cancellation is maintained over an ultra-wide frequency band.