FD-TD analysis of electromagnetic radiation from modules-on-backplane configurations

The electromagnetic radiation from a modules-on-backplane configuration found in computers is analyzed by means of the finite-difference time-domain (FD-TD) technique. The issues pertaining to the effects of the modules in influencing the overall radiating capacity of the configuration are addressed. Analyses are facilitated by using simplified modules-on-backplane models and by using a voltage source as the source of electromagnetic energy at a connector between a module and the backplane. The potential for enhancement of spurious emissions by the module-on-backplane configuration is demonstrated. For modules of typical dimensions, resonance is observed at the hundreds of MHz frequency range. Comparisons between numerical predictions and measurements are conducted to validate the numerical method