导　　师： 谢康

学科专业： 0803

授予学位： 硕士

作　　者： ;

机构地区： 电子科技大学

摘　　要： 光子晶体是一种具有频率禁带的新型周期结构。根据禁带形成机理的不同,分为布拉格散射型光子晶体和谐振型光子晶体。本文主要研究谐振型微波光子晶体及其在微带天线中的应用。 本文的工作重点是以高阻表面为代表的谐振型光子晶体带隙特性研究和光子晶体天线的设计。首先综述了光子晶体的概念、分类、分析方法及其目前的应用概况。然后阐述了光子晶体的基本理论、高阻表面光子晶体的等效介质模型以及微带天线的基本原理。在此基础上,主要研究了以下内容: /(1/)研究了方形贴片单元的高阻抗表面光子晶体,针对贴片单元边长、贴片的间距、基板厚度、基板介电常数、以及过孔尺寸对入射电磁波反射相位的影响进行了仿真分析。 /(2/)采用三层高阻抗表面结构实现了2.45GHz频段的高阻抗表面光子晶体的小型化。 /(3/)光子晶体在微带天线中的应用。仿真结果表明,加载光子晶体结构后的天线提高了主辐射方向的增益,降低了副瓣电平,减小了天线单元之间的互耦。同时可以看到当表面波功率较大时,微带天线的性能改善更为明显。计算结果由商业软件HFSS仿真得到。 Photonic Crystal is a new type periodic structure which has frequency bandgaps, and the propagation of electromagnetic waves whose frequencies are within the bandgaps is forbidden. According to the different formation mechanism of band-gap, photonic crystals can be divided into two types which are Bragg scattering-type and resonant-type. This dissertation studies resonant-type photonic crystal in microwave band and its application in microstrip antenna. This dissertation focuses on the electromagnetic characteristics of High impedance surface /(HIS/) which is a representative of resonance-type photonic crystals and the application in microstrip antenna. First of all, the concept of photonic crystal, classification, analysis method and overview of its current application are reviewed. Then the basic theory of photonic crystals, effective medium model of HIS photonic crystal and the basic principles of the microstrip antenna are Described. On this basis, the primary work is as follows: /(1/) For HIS photonic crystal, the cells with Square patches are Studied in detail. Some parameters which can affect the bandgap characteristics of the HIS have been studied, including cell size, gap width, Via size, thickness and dielectric constant of substrate. /(2/) Miniaturization of HIS photonic crystal is achieved in 2.45GHz frequency band using three-layer structure. /(3/) The photonic crystals have been applied in microstrip antennas. Simulation results show that the gain of the main radiation direction with PBG structures is increased and the sidelobe level is reduced, the mutual coupling between antennas is reduced also. The results also show that the performance improvement of the microstrip antenna is more obvious when the surface wave power is larger. All of the computed results are acquired by simulation. The job is done by the commercial software HFSS.

关 键 词： 光子晶体 反射相位 微带天线 表面波

领　　域： [理学] [电子电信]