Integrated Physical Optics for Calculating Electric-Large Metallic Sphere Scattering Irradiated by Vortex Wave in Microwave Frequency Band

In this letter, a novel integrated PO (physical optics) method for calculating high frequency scattering of non-plane wave is proposed, and the OAM (orbital angular momentum) wave scattering upon an electric-large metallic sphere is illustrated. A high order Bessel wave expanded by a series of plane wave angular spectra is selected to irradiate a PEC (perfect electric conductor) sphere. Combining the PO approximation, the scattered field from the facet element is calculated, and the total scattered effect is obtained by vector superposition of the scattering from all facets. The calculated results are verified by the EM simulated software FEKO and scattering measurement experiment. Numerical results show that the scattered field of the vortex wave passing through the standard target still has the OAM characteristics, retaining the same topological charge. It can be seen that the proposed combined PO method is feasible at high frequency and can be extended to solve the scattering of other beams and objects, which has a broad range of applications.