This communication presents a method to ease the computational burden of simulating antennas radiating close to dielectric bodies, e.g., dielectric lenses. The input impedance can be split into the capacitance of the feeding gap, a term associated with the propagation in dielectric half-space, and a term associated with the reflections created by the finite dielectric. These three terms are independent of each other and can be calculated separately. The capacitance of the feed and the term associated with radiation in the absence of the reflections can be easily evaluated. A feed with coarser detail and having the same interaction with the lens is then synthesized. This allows us to estimate the reflection from the lens efficiently, and then the different terms are recombined to estimate the total input impedance.

A spectral domain analysis aimed at studying dipoles radiating in layered media is presented. The model allows for the modeling of the non-zero metal thickness and the reactance associated with a Δ-gap excitation. The solution can be efficiently calculated with a semi-analytical procedure, and it is linked to an equivalent circuit representation. The results show an accuracy up to par with commercial solvers regarding the input impedance and the radiated far field patterns.