Modular fast direct analysis method applied to connected platform and design structures

The modular fast direct analysis (MFD) method has been proposed to deal with a class of electromagnetic design problems that involve a fixed platform structure, which dominates the problem size, and a fixed design region that contains variable design structures. The former reported work focused on showing the efficiency of the MFD method and worked with separated platform and design regions. The Green box runs through the gap between the platform and design regions. Such arrangement avoids evaluating the singular interactions between structures and the Green-box because they can be well separated. In this paper, it is shown that the singular interactions can be avoided even for connected platform and design structures with the introduction of a buffer region.