Analysis of emission from a slot nearby a microstrip line on a printed circuit board

By advance of miniaturization of electronic devices, a ground plane of a printed circuit board is tend to be small and complicated and the ground plane may have some defects, such as connectors or clearance halls of vias. In this paper, we analyzed the coupling between a microstrip line and a slot in a ground on a PCB using the MTL method to examine an effect of the signal integrity for the slot in the ground. Especially, in order to increase the accuracy the per-unit-length self conductance of the slot line was considered. And also we analyzed emission from a PCB with slot using coupling slot voltages which was calculated by the MTL method. To calculate by using the MTL method, some self and mutual parameters of a microstrip line and a slot were calculated using the FDTD method. Finally, we showed the validity of the method in this paper, comparing results using the MTL method with numerical results using the FDTD method. It is shown that the proposed method is validated by comparing results by the MTL method with results by the FDTD.