ADS vs CST

Hi Guys,
I am simulate branch line.
F (center)=1G
I did it in Momentum (ADS)
after that I simulate the same design in CST (both T domain and F domain)
Results are different!
For example,
In Ads I got S11, S22 (returnloss) >=20dB
In CST >= 10dB
IL in ADS differnece of 0.5 db
IL in CST 1.5dB
Which simulator more accurate.
PS:
In CST like i said I simulate both T domain and F domain
they pretty simulator (IL 0.5, RL 5dB difference)
David

CST simulation results are decided by its mesh compression.
You can try hfss, it's accurate even if you use its default setting.

Yes i know
So when I simulated in CST meshcelles was changed to 2.3e6
Pretty good mesh!
David

The difference could be caused by many reasons. WinRAR your design files and upload here.

Hi
my experience with CST is that adaptive meshing should be used for accurate results.
flyhigh

As per my experience Momentum results should be more accurate. It will be better if you can upload project here.

I would say either you use HFSS or CST, it doesnot yield a lot of difference in results. However, working with ADS, you should specify whether you used Analytical Models or Momentum designs. The Analytical results (if not properly taken into account other effects) are far from the results you could achieve in practice. It might be representing a lower bound of performance curves. Momentum results are therefore much more realistic based on 3D-planar simulations, should therefore be close to either CST or HFSS, a full 3D simulation.
regards,