Modeling and Analysis of Vertical Vias in High Speed Printed Circuit Board
高速印刷电路板间垂直通孔的建模与分析

Vias are one of the most common interconnection structures used in modern high speed Printed Circuit Board (PCB), which would induce a series of problems such as loss of signal integrity when transmitting signal especially high speed signal. So it is very important that vias are modeled and simulated accurately, speedily, efficiently. The network cascade theory combined with a semi-analytical full wave approach based on Foldy-Lax equation is used to model vias in this paper. In single-layer vertical vias, the Fold-Lax equations of multiple scattering among the cylindrical vias are given. The exciting field coefficients of cylindrical vias are solved. The scattering matrix of coupling among single-layer vias is calculated. By multi-port network cascade theory, the scattering matrix of coupling among multi-layer vertical vias is obtained. The results of scattering matrix are given for 4-layer vertical vias, which show that the method presented in this paper is correct and valid.