Reduced-order modeling of an electromagnetic system is understood as the ap
proximation of a continuous or discrete model of the system by one of subst
antially lower order, get capable of capturing the electromagnetic behavior
of the original one with sufficient engineering accuracy. Specific methodo
logies for model order reduction of distributed electromagnetic systems are
discussed in this paper. It is shown that electromagnetic model order redu
ction enhances computational efficiency and, thus, facilitates system-level
modeling and computer simulation of multifunctional systems, The proposed
methodologies are demonstrated through applications to the reduced-order mo
deling of high-speed interconnects, electromagnetic waveguides, and microst
rip antennas.