Analysis and Design of Volume Photonic Metal Grid Antenna Elements

0096395 Makarov提出了一个为期两年的计划，研究有限矩形体积金属网格的传输，散射和聚焦现象。网格单元尺寸为波长量级或更小。该项目的成果将有助于开发大型天线，包括基站天线，卫星天线和雷达。其中一个影响可能是用具有频率选择反射特性的特殊设计的3D金属网格代替反射金属片或微小的金属纹理。数值和理论分析将占项目工作的65%，而实验将消耗剩余的35%。 今天，有限金属网格（和任何有限光子晶体）的数值建模构成了相当大的困难，是非常耗时的。数值求解器的速度问题是设计过程中最关键的参数：可能需要数百次试验才能确定合适的金属网格结构。作为该建议的一部分，将开发一种新的磁场/电场积分方程的迭代求解器。它的思想是将原方程转换为标准（能量）形式，然后应用广义最小残差（GMRES）优化。当前求解器性能在项目描述中报告。初步研究表明，求解器是快速的，需要几十个迭代复杂的金属网格结构。到目前为止，求解器使用最简单的（分段常数）基函数，没有特殊的反共振技术。因此，该项目的第一个目标是修改和进一步开发求解器，以便能够在20-40次迭代中计算具有100-225个单元和2 x 10的5次方-1 x 10的6次方边界元素的谐振体积金属网格。 接下来，将对三个网格参数进行广泛的数值模拟：单元间距、厚度和深度。第四个参数是弯曲网格的网格曲率或成形网格的成形因子。建议的建模工作的目标是：i。各种网格模式的透射光谱路线图。寻找具有特殊传输/聚焦特性的成形网格，包括比等效固体反射器或透镜更高的聚焦增益。第一个目标正在成为光子金属/介质滤波器开发的标准步骤。本项目所需的通带特性将使用工业链路来确定。第二个目标更值得怀疑，但如项目说明所述，可能带来重大好处。实验部分的工作包括制造的金属网格，传输光谱测量使用网络分析仪和两个小喇叭天线，和表面电流分布测量网格使用红外探测系统和高功率微波饲料。该提案包括一个实质性的教育部分，面向一般天线理论。该教学计划预计一个研究生（两年）的天线设计，一个或两个短期的本科项目，并纳入天线相关的材料到本科和研究生课程的快速矩量法项目，特别强调遗传优化算法。作为教学计划的结果，将创建一个用于Matlab的介绍性天线工具箱。工具箱将包括接收和发射（三角形间隙馈电）天线元件，如导线、矩形导线网、板和可能的凸反射器。

0096395MakarovA two-year program to investigate transmitting, scattering, and focusing phenomena of finite rectangular volume metal grids is proposed. The grid cell sizes are on the order of a wavelength or smaller. The project results will make a contribution to the development of large-scale antennas, including base station antennas, satellite antennas, and radars. One of the impacts could be the replacement of a reflecting metal sheet or a tiny metal texture by a specially designed 3D metal grid with frequency-selective reflectivity properties. Numerical and theoretical analyses will take up 65% of the project work while experimentations will consume the remaining 35%. Today, numerical modeling of finite metal grids (and of any finite photonic crystals) constitutes considerable difficulties and is very time consuming. The speed issue of a numerical solver is a most critical parameter for the design process: many hundreds of trials may be necessary to identify a proper metal grid structure. As part of this proposal, a new iterative solver for magnetic/electric field integral equations will be developed. Its idea is to convert the primary equation to the normal (energy) form and then apply a generalized minimum residual (GMRES) optimization. The current solver performance is reported in the project description. Preliminary studies indicate that the solver is fast and requires a few tens of iterations for complicated metal grid structures. To date the solver uses the simplest (piecewise-constant) basis functions and none of the special anti-resonant techniques. The first goal of the project is therefore a modification and further development of the solver in order to be able to compute resonant volume metal grids with 100-225 cells and with 2 x 10 to the fifth power - 1 x 10 to the sixth power boundary elements in 20-40 iterations. Next, extensive numerical modeling will be performed with respect to three grid parameters: cell spacing, thickness, and depth. The fourth parameter is grid curvature for curved meshes or a shaping factor for shaped grids. The objectives of the proposed modeling efforts are: i. Roadmaps of transmission spectra for various grid patterns.ii. Search for shaped grids providing unusual transmission/focusing properties, including higher focusing gain than equivalent solid reflectors or lenses.The first objective is becoming the standard step in the development of photonic metallic/dielectric filters. The desired pass band properties for the present project will beidentified using industrial links. The second objective is more questionable, but, as explained in the project description, may offer significant benefits. The experimental part of the work includes fabrication of the metal grids, transmission spectra measurements using a network analyzer and two small horn antennas, and surface current distribution measurements on the grid using an infrared detection system and a high-power microwave feed.The proposal includes a substantial educational component geared toward general antenna theory. The teaching plan foresees one graduate (two years) project on a fast method of moments for antenna design, one or two short undergraduate projects, and incorporation of antenna-related materials into undergraduate and graduate courses, with particular emphasis on genetic optimization algorithms. As a result of the teaching plan, an introductory inantenna toolboxla for Matlab will be created. The toolbox will include receiving and transmitting (delta gap feed) antenna elements such as wires, rectangular meshes of wires,plates, and possibly convex reflectors.