Multi-Trace Formulation of Internally Combined Volume-Surface Integral Equations

In this contribution, volume-surface integral equations (VSIE) are incorporated into the global multi-trace method. This extends multi-trace modelling to scattering on composite structures, that also have parts with non-homogeneous properties. It is shown, the volume-surface integral equations modeling these regions can be integrated in the framework of the multi-trace formulation. Due to the nature of the multi-trace method, the interior of the non-homogeneous regions only interacts internally with its boundary. There are no interactions between a region and the interior of another region. Further, the block structure of the multi-trace method is retained, which allows the use Calderon preconditioning.