3D Simulation of Infinite Baffle Diffraction

Diffraction formulations have infinite boundaries whereas simulations are solved with strictly limited dimensions. Consequently, the simulation of diffraction effects is challenging. Here, 3D electromagnetic simulations are described and compared against theoretical results for the diffraction of normally incident plane waves onto semi-infinite and infinite strip baffles. A detailed description is provided of the 3D simulation configuration necessary to successfully simulate the model. A simple expression is presented for the diffraction of an infinite strip. We show that it is possible to achieve excellent agreement between the Uniform Geometrical Theory of Diffraction and simulations. Accurate simulation results were only achieved by using the frequency domain with periodic boundary conditions and appropriately handling the bottom boundary for semi-infinite baffle diffraction.