Periodic finite-ground microstrip line with high-impedance offset sections: enhanced electromagnetic bandgap

A periodic finite-ground microstrip line (FGMSL) is proposed to make up an improved class of 1D transmission line electromagnetic bandgap (EBG) structures with enhanced bandwidth. For this purpose, the two effective unit-length transmission parameters are numerically extracted by using the full-wave self-calibrated method of moment (MoM) so as to demonstrate the complete guided-wave characteristics in comparison with those of the conventional EBG microstrip line (MSL). Subsequently, transmission coefficients (S₂₁) of finite-length FGMSL EBG structures, which are ideally matched with the two feed lines in impedance, are numerically derived to provide a straightforward insight into the guided-wave propagation characteristics and exhibit the distinctive dispersion, bandstop and bandpass behavior as the guided-wave propagates across this equivalent 1D transmission line medium.