A broadband measurement system is developed to address the issue of temperature dependence of the complex permittivity and conductivity of low-loss substrates in the millimeter-wave bands for fifth/sixth generation wireless communication applications. The developed system can provide broadband material measurements from less than 20 GHz to over 100 GHz over variable temperatures by utilizing higher order mode resonances of a balanced-type circular disk resonator (BCDR). The broadband measurement capability of the developed system is attributed to the mode-selective behavior of the BCDR over a wideband. To demonstrate the developed system, we measure the complex permittivity of the following three substrate materials over variable temperatures from $25$ °C to $100\hspace{0.17em}°$C: cyclo-olefin polymer (COP), ceramic-filled polytetrafluoroethylene composites, and fused silica. Furthermore, the temperature dependence of the conductivity of the surface-mounted metal is characterized for the COP substrate. The measurements indicate that the loss tangents and conductivities of the substrates increase and decrease, respectively, with the temperature and frequency in the millimeter-wave bands. The full-wave simulations using the measured complex permittivity and conductivity of the COP substrate reveal that the propagation loss of the microstrip line using the COP substrate increases with the temperature and frequency and that the increase in the loss is primarily attributed to the decrease in the conductivity.

中文翻译：

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使用平衡型圆盘谐振器在可变温度范围内测量毫米波段中的宽带复介电常数和电导率

开发了一种宽带测量系统，以解决第五/第六代无线通信应用中毫米波段低损耗基板的复介电常数和电导率的温度依赖性问题。通过利用平衡型圆盘谐振器 (BCDR) 的高阶模式谐振，开发的系统可以在可变温度下提供从 20 GHz 以下到 100 GHz 以上的宽带材料测量。所开发系统的宽带测量能力归因于 BCDR 在宽带上的模式选择行为。为了演示开发的系统，我们测量了以下三种基板材料在不同温度下的复介电常数：$25$ °C 至 $100\hspace{0.17em}°$C：环烯烃聚合物 (COP)、陶瓷填充的聚四氟乙烯复合材料和熔融石英。此外，表面安装金属的电导率的温度依赖性是 COP 基板的特征。测量结果表明，基板的损耗角正切和电导率分别随着毫米波波段的温度和频率而增加和减少。使用测量的 COP 衬底的复介电常数和电导率的全波模拟表明，使用 COP 衬底的微带线的传播损耗随着温度和频率的增加而增加，并且损耗的增加主要归因于电导率。