低复杂度时空调制超表面设计方法与应用  

Low complexity design method of space-time modulated metasurface and its applications

作　　者：房欣宇 朱泳庚 赖梓扬 李猛猛[1] FANG Xinyu;ZHU Yonggeng;LAI Ziyang;LI Mengmeng(Nanjing University of Science and Technology,Nanjing 210094,China)

机构地区：[1]南京理工大学,南京210094

出　　处：《电波科学学报》2022年第6期992-999,共8页Chinese Journal of Radio Science

基　　金：国家重点研发计划政府间国际科技创新合作重点专项(2022YFE0122300);国家自然科学基金(61871222,61890541,6222108);中央高校基本科研基金(30921011101)。

摘　　要：为利用超表面实现空频域电磁波的高效调控,提出了一种基于解析优化的时空调制超表面设计方法.根据调控需求引入理想时变散射系数;采用矩形脉冲离散时变散射系数,并根据所需电磁响应设计超表面单元结构;进行傅里叶展开,对每个脉冲的状态、起始时刻、脉冲宽度等进行解析优化,保留目标阶谐波,消去其他阶谐波.解析和仿真结果具有较好的一致性,表明了设计方法的可行性与准确性.该设计方法深入地研究了时空调制对空频域电磁波的调控机理,为时空调制超表面在雷达、通信等领域的应用提供了新的设计思路.In order to manipulate electromagnetic wave in both space and frequency domain using metasurface,this paper presents an analytical method which can solve space-time modulation design.Firstly,the ideal time-varying scattering coefficient is introduced according to the requirements of manipulation.Then,a series of rectangular pulses are used to discretize the ideal coefficient,and the unit-cell with specific responses are designed accordingly;Fourier series is implemented to highlight the contribution of the different frequency harmonics.The state of response,start time,and width of each pulse are optimized analytically,to only keep the desired harmonic and suppress the unwanted ones.The agreement of analytical and full-wave simulation results provides strong support for the validation and accuracy of the proposed method.The mechanism of electromagnetic wave control,in space/frequency domain,based on space-time modulation is studied intensively in this method,which may pave a new way for the applications of space-time modulated metasurface in radar,communication and other fields.

关 键 词：时间调制 空时四维调制 超表面 超材料 电磁波调控 

分 类 号：TN826[电子电信—信息与通信工程]