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.

The calculation of the transmission line Green’s function (TL GF) of an infinite metal line of rectangular cross section embedded in a generalized stratification is presented. The proposed procedure is quasi-analytical and extends prior models to account effectively for the nonzero thickness of the conductors. From Green’s function of an infinite dipole, an equivalent network is derived to represent the current propagating along the dipole and the reactive loading due to the feeding gap dimensions. The method is validated with numerical simulations and available experimental results. Examples of dipoles in free space, microstrips, and leaky dipoles are shown.