[[Image:FDTD133.png]]
Figure 1: [[FDTD Module]]'s Far Field Background Medium dialog.
Note that the current version of EM.Cube's [[FDTD Module]] does not calculate the far-field Green's function of a laterally infinite, conductor-backed, dielectric substrate with a finite layer thickness. For problems of this type, you should use EM.Cube's [[Planar Module]]. In FDTD, either your PEC/PMC ground can be infinite or you can assume a dielectric half-space ground. Also, note that when infinite lateral dimensions are not required, like in the case of patch antennas with a finite substrate and finite ground, FDTD is the method of choice, as the planar MoM method cannot handle such cases.
{| style="width: 600px" border="1" cellspacing="1" cellpadding="1"|[[Image:fdtd_out36_tn.png]]|[[Image:fdtd_out37_tn.png]]|-|[[Image:fdtd_out38_tn.png]]|[[Image:fdtd_out39_tn.png]]|}
[[Image:fdtd_out38_tn.png]] [[Image:fdtd_out39_tn.png]] Figure 2: Radiation pattern of (Upper Left) a vertical short dipole above a PEC ground, (Upper Right) a vertical short dipole above a PMC ground, (Lower Left) a horizontal short dipole above a PEC ground, and (Lower Right) a horizontal short dipole above a PMC ground. The bottom (-Z) boundary is set to PEC or PMC, even though it is not visible.
===Radar Cross Section===