Design And Analysis Of A Two-dimension And Single-sided Left-handed Material Based On ?-shaped Structure

The left-handed material is a type of artificial medium that is synthesized according to a certain structure and has a negative dielectric constant ? and a negative magnetic permeability ? in the range of a specific electromagnetic frequency band.The singular nature of this material can play an important role in microwaves,antennas,radio frequency and optics.As a kind of artificial medium,the preparation of the left-handed material usually embeds the designed geometric resonance structure in the general medium,and combines to form the electromagnetic property that the natural medium does not have.Based on the design of left-handed material,this paper presents a single-sided two-dimensional left-handed material based on ?-shaped metal strip with the advantages of two-dimensional left-handedness,high frequency band adaptability and small cell size.The relationship between the parameters of the designed structure and the electromagnetic properties of the material was also studied.The main work of the paper as follows:1 ? Described in detail the research background of the left-handed material and its electromagnetic properties.Taking the design process as a step,the modeling of left-handed material in the simulation software HFSS and the electromagnetic simulation design.A variety of methods for testing left-handed material and methods for extracting equivalent electromagnetic parameters are introduced.The algorithm defect of choosing the branch of refractive index calculation results by using the improved parameter inversion algorithm based on Kramers-Kronig relation to solve the traditional parameter inversion algorithm is studied.2?A single-sided two-dimensional left-handed material based on a ?-shaped metal strip is designed.The structure combines two ?-shaped metal strips into a ?-shaped unit structure and consists of 16 ?-shaped unit structures periodically arranged on a single FR4 medium plate Surface,with a wide band,low loss,small cell size and other advantages.When the incident waves are incident along the X,Y direction of the dielectric plate respectively,the equivalent refractive index is realized in the 7.4GHz-14.06 GHz and 8.38GHz-15.83 GHz frequency bands,the equivalent permittivity and the equivalent permeability are simultaneously negative,The bandwidth of the passband in the two-dimensional direction reaches 5.68 GHz.3?Processing out the design by PCB technology.Test the structure's performance via the system of waveguide-vector network analyzer.Place the material in a waveguide,and the S parameters were extracted by a vector network analyzer which connected the simple with a coaxial line.Then,we can extract the constitutive parameters to verify the sample's left-handed characteristic.Finally,we provided an easy-to-process,high-performance,excellent-band-adaptable solution for the application of left-handed materials.4 ? Further study of the material structure and material constitutive parameters of the relationship.It is verified that the width of the ?-shaped metal strips constituting the left-hand material structure is increased by 0.1 mm respectively,and that the left-handed material characteristics achieve frequency shifts of 0.23 GHz and 0.1 GHz in the X and Y directions.The left-handed material constitutive parameters of the left-handed material with the left-handed material with a 2?2 arrangement are validated in the two-dimensional directions between 15.7GHz and 20.8GHz Left-handed features.To further solve the current left-handed material narrow band,poor adaptability shortcomings.