Simplified modeling of parallel plate resonances on multilayer printed circuit boards

Multilayer printed circuit boards (PCBs) are currently used in various area s of electronics such as telecommunications. However, high crosstalk betwee n signal vias can cause degradation of performance for these kinds of struc tures. Resonances of parallel ground or power planes can increase this cros stalk, In this study, a simplified approach to the modeling of these resona nces is described. It is assumed that the fields inside the board have char acteristically only two-dimensional (2-D) variation, When this hypothesis i s valid, it is shown that resonances can be measured on two-layer prototypi ng boards and simulated using a 2-D finite-difference model, It is addition ally noted that a previously suggested method of using coaxial ground vias to suppress coupling between vias is not necessarily effective if there are resonant parallel plates on the board. Agreement between measured and mode led results is good enough for practical design purposes. The main advantag es of the method used in this study compared to the more robust three-dimen sional (3-D) simulation models are savings in time and costs. Additionally, prototyping is much easier on two than multilayer boards.