Incorporating the G-TFSF Concept into the Analytic Field Propagation TFSF Method

Previously, Anantha and Taflove reported a generalized total-field/scattered-field (G-TFSF) formulation that was developed to facilitate the study of infinite scatterers, such as wedges [IEEE Trans. Antennas and Propag., vol. 50, no. 10, 1337-1349, Oct. 2002]. The G-TFSF formulation relied upon having the TFSF boundary embedded within a perfectly matched layer (PML). To account for the PML, the incident-field terms that appear in the update equations for nodes adjacent to the TFSF boundary were scaled by a constant in accordance with the amount of attenuation produced by the PML. In this work we describe how the analytic field propagation TFSF (AFP TFSF) formulation can be used in a G-TFSF-like way. This new approach possesses various advantages over the previously presented work. For example, owing to the dispersion inherent in PML's, the spectral components of pulsed excitation propagate at the different speeds within the PML. This dispersive behavior can be accommodated in the AFP-based formulation but not in the original G-TFSF implementation. Additionally, the AFP-based technique can directly model the infinite nature of objects, such as wedges, so that corners need not be embedded within the PML.