Goodness evaluation of a PCB ground plane by its resonance inside an enclosure

The ground plane plays a major role in a printed circuit board (PCB) EMC characteristics but usually its effect can not be evaluated until the final design stages when the circuit is finished and the EMC tests are carried out. In this paper a new method to evaluate the PCB ground plane goodness at earlier design stages is presented. The method uses an indirect measurement of the power dissipated by the PCB based on the resonance inside an enclosure. The radiated EMI from several PCB showing a good correlation with the resonance measurement are presented.