ABSTRACT The present work focuses on the radiation field excited by a horizontal electric dipole (HED) in a four-layered region composed of a perfect conductor covered with two dielectrics and the air above. Analytical expressions for the radiation field are derived for the case of both the source and the observation point being on or near the air-dielectric boundary. The propagation characteristics of the interference phenomenon are investigated. The radiation field components undergo sharp interference as the relative permittivities and dielectric layer thicknesses increase. When the observation angle , the trapped surface wave predominates in the total field. Otherwise, the total field is determined primarily by the lateral wave. Due to the useful applications for microstrip antennas, radiation patterns of a patch antenna with specific current distributions are investigated. Some special cases of interest are discussed. The proposed formulas offer the potential to develop planar four-layered circuit structures.

中文翻译：

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四层区域水平电偶极子的辐射方向图及其在微带天线中的应用

摘要目前的工作重点是由水平电偶极子 (HED) 在四层区域激发的辐射场，该区域由覆盖有两个电介质的完美导体和上方的空气组成。辐射场的解析表达式是针对源和观察点都在空气-电介质边界上或附近的情况导出的。研究了干扰现象的传播特性。随着相对介电常数和介电层厚度的增加，辐射场分量会受到强烈干扰。当观测角为 时，被困面波在总场中占优势。否则，总场主要由横向波决定。由于微带天线的有用应用，研究了具有特定电流分布的贴片天线的辐射模式。讨论了一些感兴趣的特殊情况。所提出的公式提供了开发平面四层电路结构的潜力。