On deembedding of port discontinuities in full-wave CAD models of multiport circuits

A systematic numerical methodology is proposed for the accurate deembedding of multiport discontinuities in full-wave numerical models of multiconductor microwave and millimeter-wave passive structures and high-speed digital interconnects. The discussed methodology is based on the earlier-proposed short-open calibration (SOC) procedure. The latter being a numerical analog of the experimental transmission-thru-reflection technique provides a consistent removal of the feed networks of the device-under-test over a wide range of frequencies. The treatment of multiport topologies is achieved through the continuation of the original scalar SOC method into the vector space. The new vector SOC method is easily combined with integral-equation-based method-of-moments electromagnetic-field solvers and allows for substantial flexibility in the choice of excitation mechanisms. Such commonly used method-of-moments driving schemes as ports locally backed up by a vertical conducting wall, ungrounded-internal differential ports, and via-mounted ports can be accurately deembedded within the framework of the vector SOC. Several numerical experiments are provided to validate the proposed multiport deembedding methodology and demonstrate its application.