Using frequency response coherent structures for model-order reduction in microwave applications

An effective practical technique for model-order reduction of large-scale linear time-invariant problems in microwave applications is presented. The reduction is performed as the Galerkin projection onto a subspace of frequency response coherent structures that contain the spectrum of the system multiinput impulse response. The subspace basis is created by the proper orthogonal decomposition of the system transfer characteristics sampled at discrete frequency points. A reduced-order modeling of an integrated planar spiral transformer is used for practical verification and comparison to the standard moment matching subspace approach.