At the present time, the package design faces demands, including the high-speed switching, low-voltage bias and minimization. The high-speed signals may induce not only signal integrity and power integrity issues, but also cause radiation and electromagnetic interference (EMI) problems. To evaluate a package design, near-field scan is a useful technique to investigate the radiation behavior. Our study is based on this near-field approach to estimate the radiation of a package by using a simulation tool. Several factors were investigated in this study. From the near-field results, we could conclude some useful concepts for package layout design.