Assessment of the Huygens' Box Method With Different Sources Near Obstacles

The Huygens' box (HB) method allows an arbitrary printed circuit board (PCB) in a simulation to be replaced with a set of current sources on a closed surface. A numerical study of the method is performed with different noise sources, represented by its HB, in combination with different obstacles. The chosen combinations mimic radiation features of real PCBs and product environments. This study shows that if the ground plane and substrate are included in the HB, the accuracy of the HB method generally is good. However, if the coupling between the PCB and the obstacle is strong, the method fails at a few resonance frequencies. In the search for the methods general limits, it is shown that the method cannot predict the maximum radiated emission of power plane resonances without including the vias in the HB.