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What are you trying to show? Do you think HFSS has different physics? No numbers in your screenshot, so this tells nothing, except that you are using the wrong calculator (one single line instead of two coupled lines with Zoe/Zoo).
EM simulation is only as good as the user's training to the tool. I am working as an RF EM simulation expert for more than 20 years, and was trying to help you here. But it seems to be a waste of time. Good luck!
I understand solver boundaries, but you misunderstood my comment. Two of your feedlines are close to the PCB edge, which is not a good idea because it changes the line impedance (in real life as well as in simulation).
If you are able to export your layout in 2D format (DXF for example), I can check using another trusted EM solver. Exporting the top layer and via is sufficient. I also need to know your PCB materials and dimensions then.
There's a bunch of different circles in your file, some are offset from the center. Below is what the DXF data looks like.
Not sure why, and what HFSS does with all that overlapping material definitions.
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Here is my model and result when using 40mil FR4 with eps_r=4.3:
The lines inside the conductor indicate the meshing, you can ignore that information. For vias I used 0.5mm diameter.
I can't comment on HFSS layout capablities, no idea. It might be user mistake, for such tools a week of training is highly recommended. My screenshots are all from ADS.
Ok, I have removed the overlapping circles within HFSS, I found out that I added them accidentally previously and they are not visible as I had told you.
But the question is even after I had removed the overlapping circles (vias) , the layout still does not behave as balun in HFSS simulation.
Then, I tried to import the DXF into ADS, but I do not know how you got around the following ADS error during simulation
ERROR: (deemif.ael line 3726, column 9)
Unable to create substrate "substrate1" in library "planar_marchand_balun_lib".
: Library "planar_marchand_balun_lib" has layout layers defined, but the units and resolution are not defined. Please use the Technology Dialog to complete the layout technology before creating a layout or substrate.
As the message says, you need to define units and resolution.
Options>Technology>Technology Setup
Use the standard settings work layout work in millimeters: units mm, database resolution 10000
Not sure how you created you workspace, usually there is a dialog upfront that asks for your choice (mm oder units).
Pins must be placed in the ADS layout editor, the port editor is then used to assign layout pins to simulation ports. Background: In some cases, EM ports might consists of multiple pins, for example in coplanar with plus and minus pins.
Sorry I can't do ADS Momentum crash course in a few forum posts. My EM trainings on site take multiple days. Keysight offer excellent trainings for layout editor basics + Momentum (3 days to 5 days).
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Here is the S21 and S31 phase for the initial DXF. Not 180° difference exactly, but in your layout the coupling segments lengths are different anyway.
Sorry I can't do ADS Momentum crash course in a few forum posts. My EM trainings on site take multiple days. Keysight offer excellent trainings for layout editor basics + Momentum (3 days to 5 days).
Sure, I'll try to answer. Maybe you can start from the ADS workspace that I uploaded - that one is complete and you can have a look at my configuration.
Don't blame the tool. From more than 20 years in EM simulation: there is a lot of possible user mistakes. New users in EM always underestimate the importance of learning the tool. Maybe HFSS support can review your model.
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