Mutual inductance is a crucial parameter in the design and optimization of coupled antennas in underground radio frequency identification (RFID) systems. In this article, a simple and accurate modeling method for determining the mutual inductance between two coaxial solenoid antennas with a large ferrite core is proposed. This proposed model is verified by comparing the results obtained from the commonly used method for small ferrite core antennas, high-precision filament method, and finite element method (FEM). An experimental setup has also been built to validate the proposed method. This new method for predicting mutual inductance has greater adaptability and higher accuracy, and is much better suitable to optimize the performance of RFID antennas with a large ferrite core.

中文翻译：

---

用于地下 RFID 应用的两个具有大型铁氧体磁芯的同轴螺线管天线的互感建模


互感是地下射频识别 (RFID) 系统耦合天线设计和优化的关键参数。本文提出了一种简单而准确的建模方法，用于确定两个具有大型铁氧体磁芯的同轴螺线管天线之间的互感。通过比较小型铁氧体磁芯天线常用方法、高精度灯丝法和有限元法（FEM）获得的结果，验证了该模型。还建立了一个实验装置来验证所提出的方法。这种预测互感的新方法具有更大的适应性和更高的精度，更适合优化大铁氧体磁芯的RFID天线的性能。