Environmental temperatures may affect the high-frequency electrical performance of passive components, including passive intermodulation (PIM) characteristics. This work proposes a theoretical model of the third-order intermodulation distortion (IM3) signal as a function of the material properties and contact characteristics in a connector. A cross-sectional model of the inner conductor supported by finite-element analysis (FEA) simulations was used to investigate the effect of temperature on the current density distribution in different material regions and its impact on nonlinear performance. Based on electrical contact theory and temperature-dependent modeling, mathematical expressions were developed to calculate the impact of the various contact parameters, such as contact pressure, contact area, and contact resistance. Combining the effects of both material nonlinearity and contact nonlinearity, the IM3 product powers resulting from coaxial connectors associated with temperature change were predicted theoretically. A series of experiments were designed and conducted to measure the IM3 product powers of connectors for a variety of environmental temperatures. The model predictions show a good correlation with these experimental results.

中文翻译：

---

环境温度对电连接器无源互调的影响

环境温度可能会影响无源组件的高频电性能，包括无源互调（PIM）特性。这项工作提出了一个三阶互调失真（IM3）信号的理论模型，该信号是连接器中材料特性和接触特性的函数。使用有限元分析（FEA）模拟支持的内部导体截面模型来研究温度对不同材料区域中电流密度分布的影响及其对非线性性能的影响。基于电接触理论和温度相关模型，开发了数学表达式来计算各种接触参数（如接触压力，接触面积和接触电阻）的影响。结合材料非线性和接触非线性的影响，理论上预测了与温度变化相关的同轴连接器产生的IM3产品功率。设计并进行了一系列实验，以测量各种环境温度下连接器的IM3产品功率。模型预测表明与这些实验结果有很好的相关性。