Cylindrical FDTD grid-compatible Green´s functions

Cylindrical grid-compatible discrete Green´s functions (DGFs), derived from the first principles of the FDTD-discretized Maxwell´s equations, are the topic of this work. These functions enable the hybridization between differential and integral equation based numerical methods. The DGF replicates the FDTD solutions, as opposed to an outright discretization of the continuous Green´s function (CGF). The cylindrical formulation is attractive since it is inherently axially symmetric, such that it fits the description of a point source.