EMI noise reduction between planes due to a signal via with a ground via at various distances

This study investigates the behavior of EMI noise reduction through a simple 2-layered printed circuit board cavity, as a ground (GND) via is placed in proximity of a signal (SIG) via. Provided that the maximum frequency of the signal´s harmonic content is known, an algorithm which predicts the maximum distance at which the GND via placement will effectively provide noise reduction has been developed. This could be used as a design guideline for PCB designers.