The relationship between common-mode radiation from the ground plane and differential-mode radiation from signal traces on the ground plane

This paper deals with contributions to overall emission of common-mode (CM) radiation from the ground plane of a printed circuit board (PCB) and differential-mode (DM) radiation from signal traces on the ground plane. We extract the CM radiation and DM radiation from the overall emission characteristics of PCBs by focusing on the observation planes and polarizations of radiation patterns of the PCBs. The relative contributions of CM radiation and DM radiation over a wide range of frequencies reflect the effect of the ground plane´s shape and the placement of signal traces on emissions by a PCB.