Efficient Modeling of Interactions Between Radiating Devices With Arbitrary Relative Positions and Orientations

A novel method to efficiently compute the interaction between two devices is proposed with the aim of accurately reproducing radiated immunity and emission tests in simulations. The technique allows an arbitrary relative position and orientation between the two devices. It relies on a single simulation (or measurement) of the radiation pattern of each device. To take rotation of the devices into account, a spherical harmonics decomposition is applied together with Wigner-D rotation matrices. The resulting procedure is practical, has a low computational cost, and shows good agreement with measurements and full-wave simulations.