Domain-decomposition technique for efficient analysis of rotationally symmetric reflector systems containing 3D structures

An efficient algorithm for analysis and optimization of rotationally symmetric reflector antennas, possibly including 3D support structures and/or waveguide components, is presented. The high efficiency is obtained by using a domain-decomposition approach where each region of space is characterized independently using a generalized admittance matrix description. The admittance matrices are obtained using circular mode-matching, higher-order 3D MoM, or a newly developed higher-order MoM for bodies of revolution (BoR-MoM). The antenna performance is rigorously evaluated by cascading the admittance matrices, which subsequently allows computation of surface currents or fields in all subdomains. The new algorithm allows fast and accurate analysis and optimization of rotationally symmetric reflectors, even in cases that would normally require a time-consuming 3D solution due to the lack of rotational symmetry.