Solving Electromagnetic Scattering from Microstrip Arrays with Multiple-Traces Surface Integral Equations

In this paper, a new multiple-traces Poggio-Miller-Chang-Harrington-Wu-Tsai (MT-PMCHWT) equation is proposed to simulate the electromagnetic scattering from microstrip structures. Different from traditional EFIE-PMCHWT method, in this new multiple-traces method, the original object can be decomposed into two independent domains i.e., the exterior region (free space) and interior region (microstrip), and Robin transmission conditions (TCs) is enforced on the interface between exterior and interior regions to ensure the continuity of fields. In comparison to the traditional EFIE-PMCHWT, this new MT-PMCHWT has a better convergence property. Because the continuity of fields is ensured by TCs, the exterior and interior regions can be discretized by non-conformal meshes, which improves the flexibility and efficiency of the proposed methods substantially.