Green´s function approach for interfacing UTD with FEM for a conformal array antenna on a large platform

A hybrid interface method is presented for analyzing complex array antennas mounted on a large platform. The antenna is characterized using the finite element method (FEM), and the radiation from the antenna is computed in the presence of the platform using the uniform geometrical theory of diffraction (UTD). The antenna is replaced by a set of equivalent sources on an interface surface that radiate in the presence of the platform. The platform is characterized by a UTD Green´s function which finds the fields at any point in space due to each equivalent source. This approach may be applied to computing the radiation pattern of the antenna, the coupling to other antennas on the same platform, or the scattering from the platform back into the source antenna.