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.