单层和双层手征介质球域中并矢格林函数理论及其应用研究

The Dyadic Green's Function Theory In One And Two Spherical Stratified Chiral Media and Its Applications

本文应用散射迭加法,首先给出了单层和双层手征介质球域中的并矢格林函数,分析了点偶极天线分别位于手征介质球心和球罩内任意位置处的辐射场特性,并且给出了辐射阻抗随手征介质球尺寸的变化规律,特别考虑了手征导纳ξ_1、ξ_2的影响;研究表明,通过改变手征介质球罩的厚度和波长之比,可以任意调节罩外辐射场的极化状态。因此,手征介质在天线工程中有广阔的应用前景。

In this paper, the dyadic Green's functions of a current source placed in one and two stratified spherical chiral media are derived first using the method of scattering superposition. The characteristics of radiated fields emitted by a point dipole antenna located at the center of chiral media sphere and on the axis of spherical chirodome are analyzed, and the figures of normalized radiation resistance with the change of chiral sphere size are given, the influence of chirality admittance (ξ1,ξ2) are especially considered. The results show that we can change the polarization state of radiated fields by changing the proportionality of chirodome thickness to wavelength, so chiral media have potential applications in the field of antenna engineering.