Fast Computation of the Dyadic Green´s Function for Layered Media via Interpolation

The use of a dyadic layered-medium Green´s function as the kernel in a method of moments (MoM) modeling problem greatly reduces the complexity of modeling a stratified medium. Compared to the free-space Green´s function, there is an additional cost of having to compute a semi-infinite Sommerfeld integral for each call to calculate the dyadic layered-medium Green´s function. This letter discusses a method to tabulate and interpolate the Green´s function as a method of reducing the impedance matrix filling time. This method can be used in conjunction with existing methods for increasing the computational speed of the Green´s functions.