The perturbation approach is presented here for the first time for the analysis of an inhomogeneous circularly polarized rectangular dielectric resonator (DR) antenna (DRA). The inhomogeneous permittivity is created by perturbing a rectangle-shaped region of different material inside the rectangular dielectric resonator antenna (RDRA). The orthogonal degenerate modes with a phase difference of $90°$, ${\mathrm{TE}}_{111}^{\mathrm{x}}$ and ${\mathrm{TE}}_{111}^{\mathrm{y}}$, are excited simultaneously for achieving circular polarization. A simple expression for the calculation of the resonant frequency and optimal axial ratio point for a circularly polarized (CP) inhomogeneous RDRA is presented here. Theoretical results obtained from the proposed theory are compared with theoretical, simulated, and experimental data available in the literature. The proposed analysis results show optimal axial ratio point calculations within a 1% range of the simulated and experimental data, which is better than the previous transverse transmission line reported method, having an error of approximately 4%. The advantages, accuracy, and simplicity of perturbation theory for DR are discussed in detail. The proposed theory can be easily extended for higher order modes and other shapes of material perturbation and anisotropic DRAs. The proposed technique will help in incorporation of the perturbation in the DR so that CP radiation can be obtained in an easy way.

中文翻译：

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使用微扰理论分析非均匀圆极化空心介质谐振器天线

这里首次介绍了微扰方法，用于分析非均匀圆极化矩形介质谐振器 (DR) 天线 (DRA)。非均匀介电常数是通过扰动矩形介电谐振器天线 (RDRA) 内部不同材料的矩形区域而产生的。具有相位差的正交简并模式$90°$, ${\mathrm{TE}}_{111}^{\mathrm{X}}$ 和 ${\mathrm{TE}}_{111}^{\mathrm{是}}$，同时被激发以实现圆极化。这里给出了计算圆极化 (CP) 非均匀 RDRA 的谐振频率和最佳轴比点的简单表达式。从提出的理论中获得的理论结果与文献中可用的理论、模拟和实验数据进行了比较。所提出的分析结果表明，在模拟和实验数据的 1% 范围内进行了最佳轴比点计算，这优于先前的横向传输线报告方法，误差约为 4%。详细讨论了 DR 微扰理论的优点、准确性和简单性。所提出的理论可以很容易地扩展到更高阶模式和其他形状的材料扰动和各向异性 DRA。