MLFMA for solving integral equations of 2-D electromagnetic problems from static to electrodynamic

A normalized two-dimensional (2-D) multilevel fast multipole algorithm (MLFMA) with a computational complexity of O(N) for the quasistatic (very low-frequency) case is developed. This normalized 2-D MLFMA can be used not only independently as in the quasi-static case, but also to solve large-scale structures with dense subgridded areas when combined with a dynamic algorithm. The null-space problem for boundary integral equations at very low frequencies is also studied. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 20: 306–311, 1999.