An Adaptive Multi-Point Fast Frequency Sweep for Large-Scale Finite Element Models

Single- and multi-point model order reduction methods constitute two complementary approaches to the fast finite element analysis of passive electromagnetic structures over wide frequency bands. This paper presents an adaptive point placement strategy for multi-point methods. Numerical experiments show that, for a given approximation error limit, the proposed algorithm produces reduced-order systems of lower dimension than single point methods. Hence, solution times for the reduced-order model are improved, which is important when large numbers of function evaluation are required, such as in parametric libraries. For large-scale problems, which are not accessible to direct solvers, even the computer runtimes for generating the reduced-order systems are superior to those of single-point methods.