Numerical investigation of techniques for reducing radiated emission of PCBs with attached cables in complex systems

Numerical simulations are used to quantify the effects of fixes such as EMI filter and grounding solutions for reducing the radiated emission from a PCB with an attached cable in a complex digital system. The numerical models adopted in the full-wave simulations of a basic PCB with an attached cable are validated by comparison with an analytical approach. The investigation shows that to reduce the radiated emission from an unshielded cable attached to a PCB placed within a shielded box, the best solution is to use common-mode filters, and connect the PCB ground plane to the chassis by a suitable number of stitches.