Design And Implementation Of Array Structures Two-dimension Left-handed Material

Left-handed materials are broadly defined as a novel artificial electromagnetic material,in which the dielectric constant ? and magnetic permeability ? are simultaneously negative over a certain frequency range,it can present a variety of unusual properties,such as negative index of refraction when the electromagnetic wave propagating.The left-handed materials can play an important role in microwave?antenna?radio frequency and optical fields for its special properties.As an artificial structure,the design of left-handed materials typically embeds geometries in traditional media materials to construct a novel electromagnetic property material undetected in nature.Focuses on this topic,a novel left-handed material with rectangular array structure is proposed in this paper.The structure has some advantages such as two-dimensional isotropy?high frequency band adaptability and so on.Also,we investigated the relationship between the parameters of the structure and the electromagnetic properties of the material.The main work of the paper as follows:1.The research background and basic characteristics of the left-handed materials are described in detail.This paper introduced the modeling of the left-handed materials?the process of electromagnetic simulation and the S parameter extraction method with a measure to ensure the uniqueness of the solution based on Kramers–Kronig relations.Then the electromagnetic parameters of the equivalent permittivity?the equivalent permeability?the refractive index and the impedance corresponding to the S parameter are calculated by programming the algorithm formula in the MATLAB software.2.Presented a novel left-handed material which can generate the equivalent negative permittivity and permeability in the two-dimensional direction by etching two kinds of rectangular metal array on the double-sided FR4 dielectric substrate.The design of the structure is simple and easy to process while the passband up to 6.4 GHz.3.The relationship between the structure size and the constitutive parameters of the material was further studied.The results prove that the left-handed material layer spacing increases from 1mm to 2mm while the frequency of the left-handed characteristic shifts 2.3 GHz.It was also verified that the width of the rectangular metal piece constituting the left-handed material structure was increased by 0.4 mm will lead to the frequency of the left-handed characteristic shifts 0.8 GHz.This will further ameliorate the left-handed material's narrow band and poor adaptability.4.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 provide an easy-to-process,high-performance,excellent-band-adaptable solution for the application of left-handed materials.