Altair Feko: What are the restrictions when using media and solution methods
This article lists the restrictions when using different types of media, coatings and solution methods.
Restrictions when using dielectrics
Solution Method | Dielectric | Layered Dielectric (2D) | Anisotropic Layered Dielectric (2D) | Anisotropic Dielectric (3D) |
MoM | Yes | Yes – properties must differ from the surrounding medium | Yes | No |
FEM | Yes | Yes - properties must differ from the surrounding medium | Outside FEM region | Yes |
FDTD | Yes – non-dispersive | No | No | Yes, biaxial |
PO | Limited reflection only No metal | Yes | No | No |
LE-PO | No | No | No | No |
RL-GO | Yes | Yes | No | No |
UTD | No | Yes (reflection only) | No | No |
Faceted UTD | No | Yes (reflection and transmission) | No | No |
CMA | Yes | Yes | Yes | No |
CBFM | No | Yes | Yes | No |
Dielectric Surface Impedance Approximation
| Yes | Yes | No | No |
VEP | Yes | Yes | No | No |
Restrictions when using metallic, impedance sheet, characterised surface and windscreen
Solution Method | Metallic | Impedance Sheet | Characterised Surface | Windscreen |
MoM | Yes | Yes | Yes | Yes |
FEM | Yes - inside and outside FEM region | Yes – inside and outside FEM region | No | Yes |
FDTD | PEC only | No | No | No |
PO | PEC only | No | No | No |
LE-PO | PEC only | No | No | No |
RL-GO | PEC only | No | Yes | No |
UTD | Yes | No | No | No |
Faceted UTD | PEC only | Yes (reflection and transmission) | Yes (reflection and transmission) | No |
CMA | Yes | Yes | No | Yes |
CBFM | Yes | Yes | No | No |
Dielectric Surface Impedance Approximation
| Yes | Yes | No | Yes |
VEP | Yes | Yes | No | No |
Restrictions when using coatings
Solution Method | Coatings | |
Electrically Thin | Electrically Thick (Single Layer Only) | |
MoM | Yes | Yes – on closed PEC region |
FEM | Yes – inside and outside FEM region | No |
FDTD | No | No |
PO | Yes | Yes |
LE-PO | No | No |
RL-GO | Yes | Yes |
UTD | Yes | Yes |
Faceted UTD | Yes | No |
CMA | Yes | No |
CBFM | Yes | No |
Dielectric Surface Impedance Approximation
| No | No |
VEP | Yes | No |