This paper explores an original study of bandpass (BP) negative group delay (NGD) robustness applied to the ring-stub passive circuit. The proof of concept (PoC) circuit is constituted by a ring associated with the open-end stub implemented in microstrip technology. An innovative experimental setup of a temperature room containing the NGD PoC connected to a vector network analyzer is described. Then, the electrothermal data of S-parameters are measured by varying the ambient or room temperature range from 20 to 60°C, i.e. 40°C maximal variation. The empirical results of the group delay (GD), transmission and reflection coefficient mappings versus the couple (temperature, frequency) highlight how the temperature affects the BP NGD responses. An innovative electrothermal calibration technique by taking into account the interconnection cable influence is developed. The electrothermal robustness analysis is carried out by variations of the NGD center frequency, cut-off frequencies and value in function of the temperature.

本文探讨了应用于环形短截线无源电路的带通 (BP) 负群延迟 (NGD) 鲁棒性的原始研究。概念验证 (PoC) 电路由与在微带技术中实现的开放端短截线相关联的环构成。描述了包含连接到矢量网络分析仪的 NGD PoC 的温度室的创新实验设置。然后，通过在 20 至 60°C 之间改变环境或室温范围（即 40°C 的最大变化）来测量 S 参数的电热数据。群延迟 (GD)、传输和反射系数映射与耦合（温度、频率）的经验结果突出了温度如何影响 BP NGD 响应。通过考虑互连电缆的影响，开发了一种创新的电热校准技术。电热鲁棒性分析是通过 NGD 中心频率、截止频率和温度函数值的变化来进行的。