基于新型电磁材料的微带天线研究

发布时间：2018-03-29 17:31

  本文选题：微带天线　切入点：新型电磁材料　出处：《电子科技大学》2016年硕士论文

【摘要】：自新型电磁材料被提出以来,众多研究学者针对其开展了大量的研究,基于其表面波带隙和反射相位带隙提出了多种解决天线增益或极化问题的模型结构,验证了新型电磁材料在天线设计中所具有的独特优势。电磁模型的求解多为多参数、多目标、非线性问题,这使得使用基础数值方法对其进行求解存在相当的难度,而基于达尔文进化论的遗传算法能够摆脱对实际问题的依赖,将参数映射为算法中的个体向量,继而通过对个体进行适当的评估,最终实现电磁模型参数的优化,得到符合性能指标要求的结果。本文对当前研究现状进行综合阐述,基于蘑菇型电磁带隙结构展开分析,将新型电磁材料结构所具备的特殊电磁性能应用至微带天线中,实现了对天线增益性能的改善和对极化特性的转变。本文对新型电磁材料的表面波带隙特性进行了研究,全面详细分析了蘑菇型结构中各参数对表面波带隙特性的影响,包含对单元尺寸、贴片边长、缝隙尺寸、短路针半径、介质基板厚度、介质基板介电常以及加载在微带天线周围的带隙结构单元个数的分析比较,总结了针对特定需求对模型参数进行选取的一般原则。并基于此原则,结合改进的遗传算法对模型结构参数进行调整,设计了一种在5.8GHz表面波传输系数约为-9dB,具备了较优表面波抑制特性的带隙结构,将该结构加载至微带天线,将天线增益提升了1.73dB。另一方面,本文对新型电磁材料的相位反射带隙进行了研究,对不带短路针的单频带蘑菇型新型电磁材料结构中影响其反射相位带隙的参数进行了详细分析,包含对单元尺寸、贴片边长、缝隙尺寸、介质基板厚度、介质基板介电常数的分析比较,总结了在设计特定频段特定反射相位时对模型参数进行设计和调整的一般原则。并基于此原则,展开对双频带隙结构的分析,进而过渡至对极化相关反射表面的分析,提出一种矩形贴片加载椭圆环挖空形式结构,并利用优化算法对其参数进行优化,设计了一种对2.45GHz和5.8GHz频段x、y向极化入射波均能进行特定相位反射的极化相关电磁材料结构,将该结构作为双频线极化微带振子天线的反射地板,仿真得出3dB轴比带宽达到约90MHz和180MHz,实现了线极化天线向圆极化的转变。
[Abstract]:Since the new electromagnetic material was proposed, many researchers have carried out a lot of research on it. Based on the surface wave band gap and the reflected phase band gap, a variety of model structures to solve the antenna gain or polarization problem have been proposed. The unique advantages of the new electromagnetic material in antenna design are verified. The solution of electromagnetic model is mostly multi-parameter, multi-objective and nonlinear, which makes it difficult to solve the problem by using the basic numerical method. The genetic algorithm based on Darwinian evolution theory can get rid of the dependence on the actual problem and map the parameters to the individual vector in the algorithm. Then the parameters of the electromagnetic model can be optimized by the proper evaluation of the individual. The results meet the requirements of the performance index. In this paper, the current research situation is comprehensively expounded. Based on the analysis of the mushroom type electromagnetic band gap structure, the special electromagnetic properties of the new electromagnetic material structure are applied to the microstrip antenna. In this paper, the characteristics of the surface wave band gap of the new electromagnetic material are studied, and the influence of the parameters in the mushroom structure on the surface wave band gap characteristic is analyzed in detail. Including analysis and comparison of unit size, patch side length, gap size, short circuit pin radius, dielectric substrate thickness, dielectric constant of dielectric substrate, and number of bandgap structure units loaded around microstrip antenna, This paper summarizes the general principles of selecting the model parameters according to the specific requirements, and based on this principle, adjusts the structural parameters of the model with the improved genetic algorithm. A bandgap structure with a transmission coefficient of about -9dB at 5.8GHz surface wave is designed. The structure is loaded into the microstrip antenna and the antenna gain is increased by 1.73dB. on the other hand, In this paper, the phase reflection band gap of a new type electromagnetic material is studied. The parameters affecting the reflection phase band gap in the structure of a single frequency band mushroom type electromagnetic material without a short circuit pin are analyzed in detail, including the size of the unit, the length of the patch side, Through the analysis and comparison of slot size, thickness of dielectric substrate and dielectric constant of dielectric substrate, the general principles of design and adjustment of model parameters in the design of specific reflection phase in specific frequency band are summarized. Based on the analysis of the dual-band gap structure and the transition to the polarization-related reflection surface, a rectangular patch loaded elliptical annular hollowed structure is proposed, and its parameters are optimized by the optimization algorithm. In this paper, a polarization-dependent electromagnetic material structure is designed, which can reflect the polarized incident waves in the 2.45GHz and 5.8GHz bands in a specific phase. The structure is used as the reflecting floor of the dual-frequency line polarized microstrip dipole antenna. Simulation results show that the bandwidth of 3dB axis ratio reaches about 90MHz and 180MHz, which realizes the transformation from linear polarization antenna to circular polarization.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TN822

【参考文献】

中国期刊全文数据库 前10条

1 赵国华;李振华;崔炳U，

本文编号：1682128