Analysis of crosstalk in high frequency printed circuit boards in presence of via

In this paper the interference analysis of three layered printed circuit board with dielectric substrate above a ground plane in presence of a cylindrical via is described. The theoretical analysis is carried out in frequency domain for rf voltage coupling at the terminations of the traces due to the near field radiation from the via. The total Interference coupling voltages at the terminations are obtained from the reactive coupling between the traces plus the near field radiation coupling. The results are computed using MATLAB and are compared with those obtained in modeling and simulation analysis by using Ansoft HFSS software tool. The results are shown graphically and found good agreement. Although HFSS software tool is utilized for comparison purpose, the analytical method described in this paper provides a means to predict cross talk and radiated coupling without using very costly commercial software.