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I'm sure that your "termination" at the end of the bias line in simulation was different than the wire shown in the photo.
If you have multiple samples of your PCB, you could cut one board and measure the impedance into the bias path (with wire attached at the end), then compare that to your EM...
Just use the data and don't worry. The S2P data block performs correctly under all possible source and load impedances, even mixed impedance. The testbench source and load impedance can be very different from the impedance used to create the S2P block, that is perfectly valid.
The issue is that...
Make sure that you set both ports to 50 Ohm (!) when creating the S2P data.
Mixed port impedance for S2P is not supported by many tools.
Of course, in your testbench where you use the S2P elements you can use mixed port impedance, but not when creating the file itself.
The main issue is "stacking distance"
I created a patch array in my EM tool with 6 or 8 identical patches (all same size, not stepped as shown by tony).
I used probe feed so that we have no issue from meandered lines.
With 6 patches spaced at lambda/2, directivity is 14.1 dBi
With 8 patches...
Hi Tobias,
in your measurement you need to make sure that there is no gap in ground at the location that I marked with the arrows. Ideally you would solder the backside ground to the connector body or box, but it seems that your box can't be soldered. Some copper foil should be good enough...
Yes, or maybe CST allows to insert an ideal lumped inductor directly into the model without using a port. I'm using another EM tool (Empire XPU) where both options are available.
I see ... modelling the lumped L will give you the correct results except for the local fields directly around the...
What do you mean by "at the same time"? I would simulate this as separate models, to get M between inductor and plate, and then build another (full) model with two inductors to get mutual inductance between the inductors.
Don't do it.
For 99% of use cases, it is a waste of time to model the SMD inductor in such detail. Instead, use the CST inductor model which simulates the inductor as a black box. This inserts inductance into the signal path, and you can analyze your PCB as desired.
More detail is necessary...
Ok, I think tuning is your next step then.
The 14.41 GHz plot that you showed is not the resonance of resonator 1 or resonator 2, that seems to be the resonance of the line with mismatch on both ends.
Ok, there are multiple resonances, and it seems that you 14.41 GHZ E field plot shows one of them.
For which resonance frequencies did you design the two resonators? Do you have S11 and S21 results for the individual resonators also?
1713860080
As I wrote above, this is source power a default...
Before you start tuning, show us your S21 results for the total structure
1713808062
Don't forget that this is simulation only ... The EM tools use some large default value for excitation, such as 1A. It's a linear simulation, so the absolute value can be scaled to your liking.
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