Robustness study of bandpass NGD behavior of ring-stub microstrip circuit under temperature variation

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