Dual-polarized reflectarray for generating dual beams with two different orbital angular momentum modes based on independent feeds in C- and X-bands.

In this paper, a dual-band dual-polarized reflectarray for generating dual beams with respect to carrying two different orbital angular momentum (OAM) topological charges operating in the C-band in horizontal polarization and in the X-band in vertical polarization is proposed, with two separate horns performing on the two proposed bands as the feeding. The proposed reflectarray consists of two band reflective element cells operating in two orthogonal directions. Owing to the two composing elements orthogonally interleaved on the reflectarray surface, the corresponding phase compensation performance in one band can be slightly affected by the elemental resonance in another band; thus, the degree of the coupling between the elements with different-band operations can be neglected, resulting in fairly independent phase compensation. In other words, the desired OAM generation reflectarray, to some extent, can be developed based on two different frequency band OAM reflectarrays at the same aperture. In addition, simulations and measurements strongly suggest the feasibility and the validity of the approach, which provides a solid foundation for the application of multi-band reflectarrays to the multi-OAM-mode generation.