I. Introduction
The increasing demand for efficient and accurate solutions to large-scale electromagnetic problems has led to research that reconsiders the numerical evaluation of the Sommerfeld integrals (SIs) [1]–[3], which constitute the so-called half-space problem, i.e., radiation sources in the presence of two media. Rather than finding approximate analytical expressions for the Sommerfeld’s solution, as in [4]–[11], in this work, we consider the computation of the SIs numerically, similar to the work described in [12]–[19]. Moreover, we focus only on the finite part of the SIs and its properties, whereas the semi-infinite tail, which has been extensively studied in the past [15]–[18], is out of the scope of this communication. In particular, we consider strategies for evaluation of the finite part of SIs that can handle a wide range of source–observer distances, which is significant for applications in electrically large scenarios (e.g., aerospace [20] and maritime [21]).