Research On Electromagnetic Theory And Implementation Method Of The Novel Metamaterial Antenna

With the development of wireless communication systems toward high-speed,wide-band,and software-definable,RF front-ends and antennas in communication systems face enormous challenges in terms of versatility,miniaturization,and reconfigurability.The electromagnetic theory and implementation method of the novel metamaterial antenna provides an important theoretical basis and technical means for solving the above bottleneck problem.In this dissertation,the systematic study of metamaterial antennas is carried out in three aspects.Firstly,the simultaneous arbitrary vortex beam generator based on transform optics is studied.However,due to the strong anisotropy of this three-dimensional metamaterial and the large loss,the two-dimensional metamaterials(graphene metasurface)is studied.The proposed graphene metasurface can freely control the momentum of the beam,however,it lacks of reconfigurability.For the consideration of reconfigurability,the paper further studies the reconfigurable holographic metasurface based on the polarizable particle method.The main innovations of this dissertation are as follows:(1)Based on the principle of transform optics,a generator that can obtain arbitrary paths of vortex beams with different topological charges is piroposed,and the topological mode,propagation direction and allocated power of each vortex beam are tunable.(2)A graphene metasurface capable of airbitrarily controlling the spin angular momentum and the orbital angular momentum of the terahertz beam is proposed.This metasurface not only achieves 360° full range of phase coverage,but also controls two momentums simultaneously.(3)Combining the principle of polarizable particles and holographic metasurface structure,a reconfigurable holographic metasurface antenna is proposed.Based on this structure,thr-ee functions include circularly polarized beam scanning,near-field focusing and non-diffr-acting transmission are realized respectively.