Hybrid Iterative Approach Combined With Domain Decomposition for the Analysis of Large Electromagnetic Problems

In this paper, we propose a technique for the electromagnetic analysis of large objects considering the interactions between separate parts of the geometry (which in this context will be referred to as domains). A number of unknowns is associated to each domain, and only the basis functions included within the same domain are considered fully coupled (i.e., a full-wave analysis is performed for every domain, isolating it from the rest of the geometry). An iterative process is then applied to determine the total currents over the object, considering the currents induced by the external sources and those due to interactions between different domains. Once a current distribution is obtained over a given domain it is essential to identify those passive domains with which the interaction active-domain-passive-domain will yield a significant contribution to the final result (scattered field, radiation pattern, S-parameters, etc.). In this work, we utilize a ray-tracing method combined with the multipole expansion of the active currents over a number of points located on the radiating surface to speed up the solution of large and realistic problems.