Patent ID: 11962088
Assignee: ANHUI UNIVERSITY
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 4:
5. A dual-mode OAM convergence metasurface preparation method, comprising:
determining, by optimization, optimal parameters corresponding to various bit states of each of 2n (2n−1) anisotropic cell structures in two polarization directions based on a phase requirement of OAM for the anisotropic cell structures, wherein n denotes a bit number;
constructing the 2n (2n−1) anisotropic cell structures according to the optimal parameters corresponding to various bit states of the 2n (2n−1) anisotropic cell structures in two polarization directions;
determining, by optimization, optimal parameters corresponding to 2n isotropic cell structures based on a phase requirement of OAM for the isotropic cell structures;
constructing the 2n isotropic cell structures according to the optimal parameters corresponding to the 2n isotropic cell structures;
constructing, based on the 2n (2n−1) anisotropic cell structures and the 2n isotropic cell structures, the base cell array according to claim 1;
deriving a compensation phase of each base cell array of convergent vortex beams from free-space Helmholtz equation; and
constructing, based on the compensation phase of each of the base cell arrays, an OAM convergence metasurface carrying different topological charges by MATLAB.