A common framework for computational electromagnetics on three-dimensional grids

We review some representative grid-based simulation approaches for electromagnetic fields, namely the Finite Integration Technique (FIT), the Finite-Difference (FD) method, and the Finite-Element (FE) method. Recent research has revealed that these methods have strong mutual relations, and even coincide in some important cases. The theoretical framework and elegant notation of the FIT is shown to build a common basis for all three methods, and allows analyzing their similarities and differences. Finally, recently proposed sub-cell methods are discussed as one of the most important improvements concerning the modeling accuracy and efficiency of this class of simulation methods.