Common mode radiation often is the predominant contribution to the overall radiation from printed circuit boards. Since the return paths for common{mode currents are via displacement current, the proximity of the printed transmission lines to nearby metal objects become important. It is shown that common mode currents are due to the asymmetry of the printed structures , and therefore, an eeecti...

A new model for dielectric loss, suitable for time domain modeling of printed circuit boards, is proposed. The model is based on a physical relaxation model. Complete time domain modeling of skin effect and dielectric losses in FR-4 boards are demonstrated and experimentally verified. Finally, the developed model is used to predict that FR-4 boards are useful for data rates up to 10 Gb/s.

Title of Document: CHARACTERIZATION OF FR-4 PRINTED CIRCUIT BOARD LAMINATES BEFORE AND AFTER EXPOSURE TO LEAD-FREE SOLDERING CONDITIONS Ravikumar Sanapala, Master of Science, 2008 Directed By: Chair Professor, Michael G. Pecht, Department of Mechanical Engineering The transition to lead-free soldering of printed circuit boards (PCBs) using solder alloys such as Sn/Ag/Cu has resulted in higher t...