Numerical modeling of PCB power/ground plate-pairs by DGTD method taking into account decoupling capacitors

A discontinuous Galerkin time-domain (DGTD) method is proposed in this work to analyze printed circuit board (PCB) power/ground plate-pair having arbitrarily shaped anti-pads. To apply proper excitation source over the irregular anti-pad, the implemented wave port magnetic current excitation is expanded by the electric eigen-modes of the anti-pad that are calculated via either numerical approach or analytical method. Based on the orthogonality of eigen-modes, the temporal mode expansion coefficient for each mode can be conveniently extracted. Besides, considering the presence of decoupling capacitors, the whole physical system can be split into field and circuit subsystems. For the field subsystem, it is governed by the Maxwell's equations, thus it will be solved by DGTD method. For the circuit subsystem, the modified nodal analysis (MNA) is applied. In order to achieve the coupling between the field and circuit subsystems, a lumpled port is defined at the interface between the field and circuit subsystems. To verify the proposed algorithm, several representative examples are benchmarked.