A Discontinuous Galerkin Surface-Wire Integral Equation for Efficient Analysis of Coaxial-Fed Antennas

The coaxial cable is widely employed in radio frequency (RF) engineering as a crucial component for feeding or connecting structures that transmit RF signals or energy. Given its significant impact on the performance of connected devices, a high-definition mesh for coaxial-fed structures is often essential. Typically, the mesh for the inner conductor needs to be extremely fine, which can make simulations using the method of moments (MoM) quite cumbersome. To address this challenge, this communication explores the efficient simulation of coaxial-fed structures using the discontinuous Galerkin integral equation (DGIE) method. This approach allows for the independent meshing of inner conductors and other surfaces. Furthermore, by assuming that the diameter of the inner conductor is electrically small, we adopt a wire model to reduce the number of unknowns in the MoM simulation. Extensive numerical examples are carried out to validate the correctness, accuracy, and robustness of the proposed DGIE scheme, where two adjacent subdomains are discretized using different kinds of basis functions.