Time and frequency domain finite element modelling of periodic structures

Our aim is to employ the finite element method (FEM) for the modelling of the propagation of guided waves along a two-dimensional metallo-dielectric periodic structure situated in a parallel-plate waveguide. Both time and frequency domain Galerkin finite element formulations are presented, based on the weighted residual formulation. Furthermore, the computational performances of the finite element time domain (FETD) and finite element frequency domain (FEFD) formulations are investigated and compared. A two-dimensional metallo-dielectric periodic structure is considered and the influence of the shape of its geometry on the guided wave is modelled. In addition to modelling the guided wave behaviour in a two-dimensional periodic parallel-plate waveguide, simulations are presented for the propagation of surface waves along open metallo-dielectric periodic structures. The perfectly matched layer (PML) is used as an absorbing layer to simulate open regions.