Effects of ground vias on high-speed signal transmission in high-speed PCB design

In the high-speed PCB design, vias has become one key structure of interconnection lines, vias equivalent to a discrete structure of the signal transmission path, lead to signal reflection, attenuation and other signal integrity issues. In this paper, vias model established through 3D electromagnetic analysis software HFSS, the effects of factors of the ground vias around signal vias such as size, number and location on high-speed signal transmission performance are investigated, respectively. The results obtained demonstrate that the signal transmission quality is better with larger diameter of ground vias; the signal transmission quality is better with smaller distance between ground vias and signal vias; the more the number of ground vias, the better signal transmission quality.