if we have two terminal in our model, that only one of them is excited by 0.5v incident and the other one is 0, is Z11 equals to load impedance (impedance of whole hfss model). Also, I want to know that the Z11 which is complex number is normalized or not? about the S11, is it V_ref/V_inc or its power? As I defined voltage in source.
Z is neither a ratio of powers, nor voltages; but formulated using both current, and voltage. So it is a full characterization using an equivalent network. Knowing the load (which is the norm for S, and T), you can derive the input impedance directly from Z. particularly, for large loads, like 120PI in antenna design, people simply approximate the input as Z11 (which is not always true, btw). Normally you don't need normalizing Z, unless comparing similar networks designed for different impedance tracts.
S are normalized to the port, which may have frequency-dependent impedance. And you can define a fixed inpedance for re-normalization in a wide band, for see-ing the pass band in general. Useful when you design with RWG-like port, but intend it for connecting to coax-port, for example.
According to the manual, the re-normalization of S is maze using Z as intermediary matrix, i.e. [S](f)->[Z]->[Sn](Zo)
It is not said, is the Z-matrix in the setup->matrix data normalized or not, but the one in modal report seems to be non-normalized. i.e. you can substitute actual (50 Ohm for instance) loads there and calculate an actual input impedance using conventional formulas.
Yes, if you have only two terminals (i.e. one port), Z11 is equal to the load impedance of the model. Z11 is a vector. S11 is V_ref/V_inc.
If you want to know whether Z11 is normalised, look at S11 on the Smith Chart. The curved lines are lines of normalised impedance Z11. If the impedance shown on the Smith Chart is the same as Z11 then Z11 is normalised (or the characteristic impedance of the circuit is 1 ohm).
The part circles are lines of constant X' and the circles are lines of constant R'. Z11'=R'+jX'
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