Multifunctional Orbital Angular Momentum Generator With High-Gain Low-Profile Broadband and Programmable Characteristics
Baiyang Liu, Sai‐Wai Wong, Kam‐Weng Tam, Xiao Zhang, Yin Li
Abstract
Transmissive and reflective metasurfaces have been extensively studied for generating an orbital angular momentum (OAM)-carrying beam. However, the existing OAM generators suffer from feed blockage, large profile, OAM mode nonreconfigurable, and narrowband. An OAM generator that integrates multiple functions into a single module is in high demand in OAM-based applications. In this study, we proposed an OAM generator based on a folded reflectarray with high-gain low-profile broadband and programmable characteristics. The proposed multifunctional OAM generator, comprising half the volume of the normal OAM metasurfaces, can generate a high-gain <inline-formula> <tex-math notation="LaTeX">$l=0$ </tex-math></inline-formula>, <inline-formula> <tex-math notation="LaTeX">$l=+1$ </tex-math></inline-formula>, and <inline-formula> <tex-math notation="LaTeX">$l=+2$ </tex-math></inline-formula> OAM-mode-reconfigurable beams with high mode purity over the frequency range of 9.5–10.5 GHz. The proposed OAM generator-integrated multiple functions have potential applications in OAM-based wireless communications and radar detection.