A Segmentation Approach for Predicting Plane Wave Coupling to PCB Structures

Evaluating the far-field radio frequency (RF) susceptibility of electronic devices often depends on extensive testing or full wave simulations. These methods are effective when complete system information is available but require substantial time and resources to evaluate a large number of variations in system configurations, where trace routings, integrated circuit (IC) package styles, trace terminations, arrival angle, and polarization of incoming wave, etc., are varied from one configuration to another. The goal of the following article is to develop simulation techniques for studying the statistical characteristics of coupling to typical printed circuit board (PCB) structures. Simulation time can be reduced by breaking the structure into small segments, determining the coupling and transmission characteristics of each segment analytically or in a full-wave model, and then determining the coupling to the overall structure by assembling the individual segments in a circuit simulation. Reusing premodeled segments of commonly occurring structures (e.g., IC package, trace, etc.) allows one to make estimates with minimal computational effort even for a complicated PCB design. Simulation time is estimated to improve by a factor of 40 or more over traditional full-wave modeling using this approach. This methodology enables the analysis of statistical electromagnetic coupling to random PCB geometries.