Numerical calibration in FDTD to compute complex reflection coefficient of periodic structures

The use of a reference load (here, a short circuit) in a finite difference time-domain method combined with Floquet boundary conditions in order to compute the complex reflection coefficient of infinite periodic structures is described. The short circuit imposes the position of a reference plane, essential for the calculation of the phase. This approach is called `numerical calibration´, by analogy with the experimental calibration of network analysers