【作者】 李响；

【导师】 杨明武；

【作者基本信息】 合肥工业大学 ， 微电子学与固体电子学， 2006， 硕士

【摘要】 本文首先对FDTD算法理论予以介绍,并对FDTD算法中电磁学问题的描述方法进行说明。进行基于FDTD算法并利用计算机可视化技术实现对目标系统进行电磁建模的研究,建立几何建模算法和网格坐标生成算法,设计出一套具有丰富内建图形处理功能的网格生成软件。 本系统将FDTD仿真软件所需要的以文本输入方式描述的电磁学问题描述文件如介质参数文件、几何建模文件、网格坐标文件、边界条件文件、输入与输出记录文件等以前需要手工输入完成的工作,利用VisualBasic语言实现为模块式的可视化方式显示,利用计算机技术完成如网格划分等繁复的工作,充分发挥建模软件所起的作用,使用户可以集中精力于模型各参数的优化以及模型结构的修改上,提高建模的效率。 系统可以直观体现出所建模型在各电磁学问题中的描述状况,尤其在网格坐标生成、网格校验功能上,能够根据用户要求自动生成所需分布形式的网格坐标并自动检测出不符合算法要求的网格坐标,使网格坐标生成准确,工作轻松、高效。系统提供模型被网格划分的三维显示,能够直观的反映出建模物体最终的网格划分状态。对于不规则物体,系统采用阶梯近似方法对其边界进行拟合并可自动生成圆柱类物体。系统对输出结果给出直观显示,采用不同线形和颜色进行多点输出的显示。 在本系统中通过对目标系统进行3D建模、对各电磁学问题进行描述,系统将生成的电磁建模文件输入FDTD仿真软件即可进行模拟分析计算。软件可以直观显示出仿真计算结果。本文以贴片天线建模及其反射系数的计算、带阻滤波器建模及其透射系数的计算以及U型天线的建模为实例,表明该电磁建模系统界面友好、操作方便、准确高效。更多还原

【Abstract】 In this paper, the FDTD algorithm for solving the MAXWELL equations is introduced. According to the the FDTD algorithm and computer visualization technology, the paper establishes the modeling algorithm and the mesh generation algorithm. The FDTD MESH Generator System (software) which has abundance of graphics’ processing functions is designed in this paper.The system describes the electromagnetic parameter files directly, such as medium file, geometry file, mesh file, boundary file, input file which described in the form of text is realized in modularization and visualized by utilizing the Visual Basic computer language.The system accomplishes some complicated assignments such as the mesh generation and the model dissection by utilizing the computer technology, so the user can concentrate on optimizing the model parameters and perfect the construction of the model.The system displays the description of the electromagnetic parameters directly, especially in mesh generation and mesh verification, it can generate the mesh in the style of users’ requirement and find out the coordinates automatically which disobey the FDTD algorithm. It provides the 3D display of the meshed model. The system adopts the staircase approach the boundary of irregular object and it can generate circular object automatically. The system displays the simulation result in different line style and color.Through modeling objects and describing electromagnetic parameters and putting electromagnetic files into FDTD simulation software, we can get the FDTD analysis result, and observe it directly. Patch antenna, BLPF and the U-shaped antenna modeled in this paper indicate that the electromagnetic modeling system is precise and efficient.更多还原