Finite element analysis of doubly curved conformal antennas with material overlays

The analysis of doubly curved conformal antennas with dielectric overlays is a challenging problem because there exist only a few geometries for which a closed form expression for the Green´s function exists. Further, even when the Green´s function is available, the presence of material overlays complicates the implementation of the moment method technique making it nearly impractical. To avoid use of the Green´s function, in this paper we present a finite element artificial absorber technique in which the near field of the antenna is modeled by the finite element method and the mesh is terminated using an artificial absorber. The latter is placed only a fraction of a wavelength away from the antenna but nevertheless it is shown that the antenna parameters can still be computed accurately.