三维周期结构复合谐振模式等效电路综合与谱域Galerkin法分析

The filtering performance and frequency response stability of most of conventional frequency selective surfaces (FSSs) are usually limited, especially for the FSS under electromagnetic wave with oblique incidence, and they are generally narrow band. Recently, 3D-FSS based on three-dimensional periodic structure is becoming an interesting and promising topic of research, which exhibits stable elliptical bandpass filtering performance with multiple transmission poles in the passband and multiple transmission zeros with wide out-of-band rejection. However, analysis methods based on the classic Floquet theorem and the equivalent circuit synthesis method from microwave filter cannot comprehensively analyze the frequency characteristics of 3D-FSS, especially for electromagnetic wave with oblique incident angle and different polarizations...The prospective project will focus on the electromagnetic characteristics analysis of three-dimensional periodic structures. At first, composite resonant mode of three-dimensional periodic structures will be investigated by establishing equivalent circuit model in both longitudinal and tangential plane. Primary functions will be chosen based on the Galerkin Method in spectral domain, and both resonance and transmission characteristics of the structures will be studied by using cyclic iterative method. Equivalent polynomial of the propagation constant and the input impedance of three-dimensional periodic structures will be given. This is the main research content of the project.And then, based on theoretical analysis, the technique to construct multiple transmission poles and multiple transmission zeros for three-dimensional periodic structures will be studied, and wideband/mutliband 3D-FSSs exhibiting elliptical bandpass filtering performance will be designed. Finally, the 3D-FSS under electromagnetic wave with oblique incidence angle and different polarizations will be investigated comprehensively. The theoretical mechanism of the frequency response instability of 3D-FSS will be given. The guidelines of improving the frequency response stability of 3D-FSS will be proposed.

传统频率选择表面（FSS）滤波性能以及频率响应稳定性均有限且带宽较窄。基于三维周期结构的3D-FSS因其可同时构造多个传输零点和传输极点以及稳定的频率响应特性而备受关注。然而基于经典Floquet定理的诸多方法和基于传统微波滤波器的等效电路综合分析方法都无法全面分析3D-FSS。.本申请项目将围绕三维周期结构的电磁特性开展理论研究工作，首先建立三维周期结构纵向与切向平面完整复合谐振模式等效电路模型，基于谱域Galerkin法选择合适基函数并应用循环迭代法计算三期周期结构谐振和传输特性及之间的关系，推导计算传播常数和输入阻抗等效多项式。然后基于理论分析寻找构造3D-FSS多个传输极点和多个零点的理论基础，并设计具有椭圆滤波频率响应特性的3D-FSS。最后全面分析电磁波斜入射和不同极化方式影响3D-FSS频率响应不稳定的理论机理，提出新型三维周期结构以提高3D-FSS的频率响应稳定性。

本项目成果电磁隐身与防护表面，与各战域装备平台前端外表面共形安装，具有空间电磁波调控能力，是实现无线系统设备隐身与防护、提高装备战场生存力关键技术。..项目聚焦高性能电磁表面研究，针对电磁隐身与防护理论与技术问题，研究各向异性电磁表面在频域（FSS）、空间域（ASS）、能量域（ESS）对电磁波调控的机理与方法，并探索融合辐射的智能一体化电磁表面（I2SS）新概念与关键技术，以装备战场生存力实际需求为导向，提高装备电磁空间顽存能力。研究了大曲率共形隐身需求下电磁波超宽角域斜入射，天线超宽带外隐身需求下超大带宽吸波-透波-散射，释放天线占有空间高集成度共形需求下辐射、隐身与防护智能一体化三个方向；完善了电磁表面基础理论，夯实了电磁表面空间电磁波调控技术，将用于指导电磁表面隐身与防护工程应用。本项目提出超宽角广义布儒斯特动态波阻抗匹配理论，实现80度透波角，突破57.8度传统理论极限值；研究多模多模态复合电磁表面波阻抗超大带宽匹配技术，实现22个倍频程带宽；提出双模态融合隐身电磁辐射表面概念，实现电磁吸收表面融合辐射功能，共形设计后波束扫描达120度。..本项目共发表SCI论文53篇，EI论文99篇，近五年发表SCI论文36篇；以第一/通讯作者在Advanced Optical Materials期刊录用论文1篇，在IEEE Transactions系列期刊发表/录用论文21篇。Google Scholar引用总1126次，SCI他引总764次，单篇文章最高SCI他引140次，得到了168位院士、IEEE Fellow正面评价。近两年在全国微波毫米波会议、国际微波与毫米波技术会议（ICMMT）、国际应用计算电磁学大会（Piers）做特邀报告三次。以第一发明人身份申请国家发明专利12项，获授权发明专利6项。..本项目成果支撑项目负责人担任通信学会组织工作委员会委员；担任《中国电子学会会员通讯》创刊编委和《北京理工大学学报（英文版）》编委，担任2022年全国微波毫米波会议、2021年国际应用计算学大会（ACES）和国际电磁场研究进展年会（Piers）分会场主席；并是IEEE、中国电子学会、通信学会高级会员。