electrical large cst

Now electric large antenna simulation is a difficult disk. I want to know whch one of cst hfss and feko is good at in the electric large antenna simulation! thanks a lot!
cheers!

Feko is OK for large problems
KMPA

Hi,
for electrical large structure (several wavelength in all directions) HFSS is out of the game. This leaves CST (or time domain in general) or FEKO (MoM)
Which software is more suitable depends on the structure itself. If you only have a small amount of metal surfaces and dielectric parts in your structure MoM will be faster because you only have to mesh the surfaces. A limited number of metal parts will lead to very few mesh cells.
If you have electrical large structures with a large amount of metal parts and dielectrics (like a complicated corrugated horn with a length of 15-20 wavelength) time domain will be better.
F.

What is FEKO special at?

Hi George137,
feko as compared to CST Microwave Studio has included in its package asymptotic high frequency techniques (e.g. Uniform theory of Diffraction; UTD and Physical Optics; PO) for use with electrically large objects. You can also use hybrid methods e.g. MoM/UTD or MoM/PO for problem solving. It is a especailly good tool for antenna placement and EMC applications. Of course it can perform many other tasks. See http://www.feko.info. Memory requirements and calculation speed for solving problems is reduced from normal Method of moments by using the MLFMM (Multiple level fast mulitpole method). It is however frequency domain so it uses surface mesh as compared to cells in time domain methods. Every different solver has its special appplications.
Regards,
Element7k

I would not say that HFSS cannot handle
large radiation problem
I could show a simulation results of very large waveguide array
of course HFSS being a professional tool giving accurate results
require a professional machine with professional characteristics

but how long did the hfss model take to simulate and on what system with how many processors and how much RAM? - not everone can afford expensive workstation solutions..... the method simply implies this regardless of what anybody might say...
hfss = high frequency small structure simulator ?

Hi,
I have seen an Ansoft presentation were they showed electrical large structures like a 12 arm power divider with 600 000 tets. Solution time was about 1.5 H (for each freq. point as far as I remember)
Computer was a Sun Enterprise 4500 with 8 Processors and 8 Gb Ram.
I check the hardware price after this presentation. At this point is was much more then 100 000 USS ! Pretty expensive if you consider that one could use any time domain code to solve the same structure on a "normal" PC.
F.