基于偶极子方环交叉元有损电容表面的薄宽带吸波器设计  

Design of Thin Wideband Absorber Based on Lossy Capacitive Surface of Dipole Square Ring Crossed Element

作　　者：林一夫 杨贤昭[1] 李享成[2] Lin Yifu;Yang Xianzhao;Li Xiangcheng(Engineering Research Center for Metallurgical Automation and Measurement Technology of Ministry of Education,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China)

机构地区：[1]武汉科技大学冶金自动化与检测技术教育部工程研究中心,湖北武汉430081 [2]武汉科技大学省部共建耐火材料与冶金国家重点实验室,湖北武汉430081

出　　处：《光学学报》2023年第3期185-193,共9页Acta Optica Sinica

基　　金：国家自然科学基金(51972242)。

摘　　要：为了解决常见吸波材料厚度大、吸波频带窄的问题,设计了一种采用新型偶极子方环交叉元结构的带宽大、厚度薄的吸波器,它由导电浆料和氧化铝陶瓷组成。基于有限差分时域方法采用CST软件仿真计算了该吸波器的电磁参数与反射率之间的关系。利用等效介质理论反演得到了吸波器的等效电磁参数与等效阻抗。通过优化偶极子方环交叉元结构的单元尺寸和电路参数,设计的吸波器在11.0~18.0 GHz频率范围内反射率小于-10 dB,厚度为1.6 mm,品质因素(FOM)远高于大多数文献报道的吸波器。研究发现该吸波器的损耗机制为共振损耗和欧姆损耗,组合频率选择表面(FSS)可以增强电磁损耗。实测结果与仿真吻合得较好,该超材料吸波器具有超薄宽带吸收的特性。Objective With the development of information technology,electronic devices are widely used while leading to many electromagnetic interference problems.In addition,useless electromagnetic waves may pose a potential threat to human health.Therefore,electromagnetic absorbing materials have been developed to eliminate electromagnetic interference and provide information security.Conventional coated absorbing materials usually have a narrow and fixed absorbing band and are susceptible to external environmental influences.Compared with traditional absorbers,metamaterial absorbers have a larger absorbing bandwidth,a stronger absorbing capacity,and a lower thickness.To solve the problem that common absorbing materials have a high thickness and a narrow absorption band,a new dipole square ring crossed element structure with a large bandwidth and a low thickness is designed in this paper.This new structure shows good stability and highfrequency characteristics.Methods In this paper,the relationship between the electromagnetic parameters and the reflectivity of the absorber is calculated by the finitedifference timedomain method through simulation with CST software.The equivalent electromagnetic parameters of the absorber are obtained by inversion according to the equivalent medium theory.The cell size and circuit parameters of the dipole square ring crossed element structure are optimized by the equivalent circuit model of the absorber.The influence of two main parameters on reflectivity is studied.The surface current,electric energy density,and magnetic energy density of a unit cell at the operating frequency are simulated to analyze the working mechanism.A highimpedance surface comprising a lossy frequency selective surface(FSS)is employed to design a broadband microwave metamaterial absorber.The dipole square ring cross element structure is designed.Conductive paste and alumina ceramic are selected as the FSS raw material and the dielectric layer,respectively.Firstly,the alumina ceramic is used to make the dielectric s

关 键 词：光学设计 偶极子方环交叉元 频率选择表面 等效介质 电磁损耗 

分 类 号：TN928[电子电信—通信与信息系统]