Solution of the canonical problem of an elementary dipole on a finite substrate using volume integral equations and volume physical optics

The far field behaviour of an elementary dipole on a one side cladded substrate is analysed as a canonical problem for the study of diffraction effects. The radiation pattern is calculated using three different methods: surface integral equations with multilayered Green´s functions, volume physical optics (VPO) and volume integral equations (VIE). Although the finiteness of the substrate is taken into account by both VPO and VIE, these methods are inherently better suited for structures on large respectively small sized substrates. To our knowledge, comparison of VPO and VIE for such a medium sized structure is completely new. It allows us to establish approximate borders and an optimal application area for each method. The simulation results show good agreement. This validates the applicability of both methods for medium sized structures and is at the same time of great importance for estimation of the backward radiation intensity of more complex antenna structures