摘 要微波光子晶体，也称为电磁带隙结构，是一种具有频率禁带的新型周期结构。本文主要针对微波光子晶体的带隙特性与其在微波天线中的应用进行了讨论。首先建立分析微波光子晶体结构的理论模型和仿真工具，讨论对象为以微带基片为载体的微波光子晶体结构。利用 Floquet 定理，将无限大周期结构简化为一个周期单元来计算。其次利用所建立的数值仿真工具，对微波光子晶体的带隙进行了计算，讨论了光子晶体在微波天线以与天线阵列中的应用。理论上证实波导缝隙相控阵天线存在扫描盲点的原因是由于天线单元之间的互耦引起的，也就是天线阵面的表面波所造成的。接着采纳光子晶体的带隙特性对天线单元之间互耦的减小进行讨论 。最后主要讨论了正方形和三角形栅格排列缝隙相控阵的仿真分析结果。讨论表明，光子晶体的引入可以有效地改善天线和天线阵列的特性，主要体现在可以减小天线单元和天线阵列间的耦合。利用光子晶体的频率带隙抑制相控阵天线单元间的互耦，改善了相控阵天线的宽角阻抗匹配，消除了相控阵天线的扫描盲点问题，从而改善天线的扫描特性。关键词：微波光子晶体，电磁带隙结构，波导端头缝隙天线，扫描盲点，宽角阻抗匹配AbstractMicrowave photonic crystals, also referred as electromagnetic bandgap (EBG) materials, are periodic structures characterized by the existence of frequency bandgaps. The dissertation focuses on the electromagnetic characteristics in microwave antenna.First,we establish theoretical model and numerical simulation method that are constructed in the microstrip structures. The infinite periodic structure is reduced to one single cell by applying Floquet theorem.Using the above simulation tools, several kind MPC structures have been analyzed。The photonic crystals (PC) have been applied in microwave antennas and antenna arrays.The reason that the scanning blind spot exists in the scanning of waveguide slotted array antenna is the coupling between antenna elements, that is, the surface wave of antenna array. Then the bandgap preperty of EBG is used to reduce the coupling between antenna elements....
