Signal Integrity and Crosstalk Analysis of PCBs Within a PEC-PMC Bandgap Metallic Cavity

The PEC-PMC type of metallic cavities has been shown to be effective to inhibit cavity resonances within well-defined bandgap limits. Such cavities are realized by appropriately placing metallic pins on the cavity lid. However, the presence of such pins, may affect the signal transmission over interconnects routed in close proximity, or right underneath the pins. The systematic analysis carried out in this paper demonstrates the feasibility of such cavities from a signal integrity and crosstalk point of view. Different distances between the pin and the traces are analyzed, such that the pinned lid is demonstrated to have not detrimental impact on the traces insertion loss. Moreover, since cavity resonances cannot occur within the bandgap, the crosstalk among traces is not affected by the cavity, thus typical PCB design and layout rules can be simply applied for the design of digital and RF interconnects.