Aliasing of electromagnetic fields in stair step boundaries Original Research Article

The effects of stair stepped boundaries on electromagnetic fields are analyzed for a cross section of a rectangular waveguide rotated in a Cartesian mesh. Spectral analysis demonstrates that stair steps introduce a rich set of aliases even in this simple case, in addition to interpolation aliasing caused by continuum wavelengths not representable on the discrete mesh. The alias effects introduce both short and long wavelengths; the latter are challenging to mitigate without apriori knowledge of the physical modes.