Electromagnetic wave scattering by two rectangular troughs on a ground plane

Electromagnetic wave scattering by two rectangular troughs on a ground plane, which is the simplest trough-grating geometry, is rigorously analyzed by using Kobayashi and Nomura's method. This method is a kind of eigenfunction expansion method in terms of Weber-Schafkeitlin type integrals. In order to show the validity of the solution, comparison with other numerical results is carried out and good agreement can be observed between them.