An Efficient Discontinuous-Galerkin Integral Method for Coaxial Cable Feeding Structures

Using coaxial cables for feeding antennas or connecting different microwave components is ubiquitous in modern microwave engineering, and the method of moments (MoM) based on integral equations is a versatile approach for accurate simulation. This paper presents a novel and efficient scheme for coaxial cable structures. To avoid extremely fine mesh for the long-thin inner conductor surface of the coaxial cable, the wire model neglecting circumferential components of currents is adopted. In addition, the discontinuous Galerkin integral equation (DGIE) scheme is developed so that conformal mesh surface-wire mesh is no longer necessary. Representative numerical examples, including a shorted-circuit coaxial cable waveguide and a coaxial cable-fed monopole antenna, are presented to demonstrate the effectiveness and accuracy of the proposed method.