Extending shooting-and-bouncing rays method with uniform theory of diffraction for installed antennas

The shooting-and-bouncing rays (SBR) method for solving large-scale radiation and scattering problems uses geometrical optics (GO) ray tracing to extend physical optics (PO) to multi-bounce geometries. In this paper, we explain how the accuracy of SBR for installed antenna geometries can be improved with the addition of uniform theory of diffraction (UTD) rays. The UTD rays provide ray coverage and paint surface currents in shadow regions, augmenting the radiation from surface currents painted by the GO rays. A realistic installed antenna application is presented as an example.