Study On Electromagnetic Vortex And Environment Scattering By Simulations

Orbital Angular Momentum(OAM)is a basic attribute of electromagnetic waves.The wave with this attribute will exhibit the spiral phase wave front,named as electromagnetic vortex.The main focus of the existing research includes the generation of electromagnetic vortex,space division multiplexing in communications and enhancement technique of radar detection,but rarely involves the scattering characteristics of propagation environment.This thesis starts with the theoretical research of electromagnetic vortex and its scattering characteristics,conducts simulation research through electromagnetic simulation software.The main research includes:Firstly,the calculation model of the electromagnetic vortex generated by the Phased Uniform Circular Array(PUCA)is established.On the basis of the model,the value range of the OAM mode of the vortex generated by PUCA is deduced.Besides,the study finds that the phase spatial distribution of the vortex is spiral.And then,using numerical simulation software for scene simulation,simulated the PUCA of 4,8,16,and 32 dipoles to generate electromagnetic vortex.The focus is on the influence of the PUCA radius of 8 and 16 dipoles on the phase space distribution.Also,it is found that the PUAC radius will affect the size of the area without phase distribution in the electromagnetic vortex.Finally,the electromagnetic vortex scattering scene is designed,and the scattering characteristics of regular geometries are analyzed through simulation.The results show that when the geometry is a sphere,the maximum value(for OAM mode as 1)of Radar Cross Section decuples the minimum value(for OAM mode as zero)of RCS;when the material is different,the RCS value of metal is higher than that of non-metal,and the maximum difference is 40 times;the maximum RCS value is obtained when the incident angle is 0,which is 4 orders of magnitude higher than the RCS value of 5?/12.