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This is related to the Z0 problem in your other post.
For wave guide ports, some 3D simulators define Z0 as line impedance at the port ("generalized S-parameters"). This means that any straight line will have perfect match, no matter what the dimensions are. However, the simulator does know that Z0 value and can re-normalize the S-parameters to 50 ohm port impedance. This is what the switch does: it allows you to switch between generalized S-parameters and 50 Ohm S-parameters.
hehe it is not that i am boring bro. It is that the numbers with "normalize to 50" ,for |s11|=0,94 with phase=14degrees, and |Zin|=|0.39+i2591|=2591 ohm and phase=89 ARE WRONG. If you take these numbers and search for Zo you will not have 50. That's my question . WHY?
Between the Z and S matrix the relation is not as simple as you write. You can not write that S11 = (Z11-Zo)/(Z11+Zo). Have a look at a HF book to see the relations. In fact you find that :
Z11 = Zo ((1+S11)(1-S22)+S12*S21)/((1-S11)(1-S22)-S12*S21))
And so on for the others parameters.
The waveguide is seen like "quadrupole" . Between the S matrix (S11 S12 S21 S22) and the Z matrix (Z11 Z12 Z21 Z22) , we have not the relation Z11 = Zo (1+S11)/(1-S11).
Refer at any book deal with filter or scatering parameters. This latest relation is true only for "dipole".