grasp em simulator

Would anyone know the basic equation on which EM simulators are working.
Like Sonnet is based on TLM ,
What about CST, Momemtum (agilent), HFSS, and others...
is it Method of Moments, Finite element Method(FEM) , Finite differential Method ....

FDTD (or FIT): CST, XFDTD
MoM: Wipl-D, IE3D, FEKO, SuperNEC, Momentum, NEC
FEM: HFSS
hybrid MoM UTD: FEKO, SuperNEC

Sonnet uses method of moment, not TLM

Sonnet Probably uses both MoM and TLM, ?

Added after 9 minutes:

Thanks Adel_48,

do you have more detail on the hybrid MoM UTD?
also what is the meaning of UTD here?

SunnySan

Nope, Microstripes from Flomerics and Mefisto are the only 2 commercial TLM codes. Sonnet used to be a distributor for Microstripes but is not anymore

also
vector fields, semcad, remcom(xfdtx) - fdtd
clasp - MoM
Ansys - FEM

Hybrid MoM/UTD means that the problem is solved using the combination of the moment method and the Uniform Theory of Diffraction (UTD). UTD is the same as GTD (Geometrical Theory of Diffraction) and is a high-frequency approximation that uses ray tracing. It assumes a plane wave and is used to calculate scattered fields on electrically large structures (> 10*lambda). Burnside and Marhefka at OSU contributed greatly to the theory of GTD/UTD (determining the correct diffraction coefficients, etc.)

Grasp is a reflector analysis tool that uses physical optics (PO), geometrical optics (GO) and GTD.

Ansoft Designer is another planar (2.5D) MoM code.

hi ,

back to Doug's info, MICROSTRIPES (3D EM Solution, TLM Method) is available directly contacting Flomerics (offices worldwide).

send a request to info@flomerics.com

good luck
AW