Abstract
This paper develops an original theory of bandpass (BP) negative group delay (NGD) function from three-port symmetric circuit. The BP NGD analysis is applied first time to three-port topology. The present study develops originally a BP NGD investigation of three-port circuit constituted by R, L and C lumped components. The equivalent S-matrix modelling is elaborated with the uncommon circuit theory. To validate the theory, a lumped circuit proof of concept is designed and simulated. A group delay value of about −0.3 ns is observed at the NGD centre frequency of about 76 MHz over 214 MHz bandwidth. For the further understanding on the BP NGD behaviour, a parametric study with the variations of the resistor, inductor and capacitor components of the Y-tree is performed. The results of the present study guarantee a potential microwave communication application of BP NGD function notably for systems operating with ISM and IEEE 802.11 standards.