UWB Antenna

hi,
I'm looking for best method for simulation of "UWB Antenna" including several patchs on a thick substrate and 2 coaxial feed line,except FDTD.
whether FIT method is suitable for this?
regards.

ragarding FIT , i think CST is better , but i only use HFSS and ie3d .
rgz
kaka

for me CST MICROWAVE STUDIO is better. also it's up to three times faster than hfss.

Can any body post the cst model for a Double-Ridged Waveguide Horn

see habib that link
https://www.edaboard.com/ftopic124038.html

CST will be fine, but my experience is the accuracy is not that good. If it is only the S11 I suggest use of HFSS. But If you need the radiated pulses, use software in the time domain, CST or XFDTD (this is FDTD) will do.