Near-zero Refractive Index Metamaterial Design And Antenna Radiation Characteristics Regulation

Recently,metamaterials are still one of the research hotspots.By arranging the artificial units in a specific way,the metamaterials may own special and anomalous electromagnetic properties,which have attracted widespread attention in various fields of basic physics,materials,optics,communication and so on.Near-zero refractive index metamaterials(NZRIMs),as an important class of metamaterials,naturally becomes a research hotspot too.NZRIMs are generally classified into the following three types,materials with near-zero permittivity,materials with near-zero permeability,and materials with permittivity and permeability close to zero.In this paper,the properties of metamaterials with near-zero permeability will be studied.Combining theoretical analysis,numerical simulation and experimental measurement,it is verified that permeability of array formed by millimeter-sized metal loops may be close to zero.Then radiation characteristics of a NZRIM planar antenna are studied.This thesis is divided into the following sections:Firstly,the research background and research significance are introduced,mainly the development process of metamaterials.Then,the characteristics of the near-zero refractive index metamaterial are described,mainly the high directivity radiation effect and the phase shaping effect.Then there is the theoretical basis of this article,the simulation tools and the content of the experimental methods and instruments,which are prepared for the later research.Thirdly,a magnetic permeability near-zero material composed of periodically arranged metal coil arrays is studied.By applying Lenz's law and Faraday's law of electromagnetic induction,,the magnetic field passes vertically through the coil array under the applied electromagnetic field,which excites the coil arrays to generate the induced magnetic field,thus making the metamaterial to have low magnetic permeability characteristics.Then using HFSS for simulation verification,the results of HFSS simulation results show that the number of turns and the size of the coil will affect the value of magnetic permeability,and the correctness of the results is verified by experiments.Finally,we studied the radiation characteristics of near-zero refractive index metamaterial planar antenna,and used HFSS to numerically simulate near-zero refractive index metamaterial planar antennas,and analyzed the radiation characteristic of near-zero refractive index metamaterials planar antennas.We have found that the length and width of the plate,the horizontal position and vertical position of the plate relative to the electromagnetic wave generator can affectthe effect of the antenna radiation.Therefore,the regulation of the radiation characteristics of the near-zero refractive index metamaterial antenna can be achieved by adjusting the position of the flat plate and the size of the flat plate.