S parameters of a connector!!

[blackout123]

Hello everyone,
I am desperately trying to find the Scattering parameters of a connector. For that purpose, I designed two lines, one of length L and the other of length 2L.
First idea was to use the T parameters to find the connector’s S parameters and the idea was as follow:
Tmeasured_L = Tc Tline Tc
Tmeasured_2L = Tc Tline Tline Tc
And then: [Tmeasured_2L] * [Tmeasured_L]-1 = Tc Tline Tc-1 = Ta
                    [Tmeasured_L]-1 * Ta = Tc-1 Tc-1
and then invert everything and square root… this is the matlab code but the result cannot be correct

Hello everyone,
I am desperately trying to find the Scattering parameters of a connector. For that purpose, I designed two lines, one of length L and the other of length 2L.
First idea was to use the T parameters to find the connector’s S parameters and the idea was as follow:
Tmeasured_L = Tc Tline Tc
Tmeasured_2L = Tc Tline Tline Tc
And then: [Tmeasured_2L] * [Tmeasured_L]-1 = Tc Tline Tc-1 = Ta
                    [Tmeasured_L]-1 * Ta = Tc-1 Tc-1
and then invert everything and square root… this is the matlab code but the result cannot be correct

[rfeecs]

This is at least the fourth time you have posted the exact same question, previously under the user name RFbeginner.

I guess you were not happy with my answer:
https://www.eevblog.com/forum/beginners/s-parameters-of-a-connector/msg2618190/#msg2618190

Your equations are wrong.  That's why your program doesn't work.

Consider this:
You have two unknown two ports: Tc and Tline
These are passive and reciprocal, so for each one S12=S21
Tline is symmetric, so S11=S22
So you have 5 unknowns:
1.  Tc(S11)
2.  Tc(S21) = Tc(S12)
3.  Tc(S22)
4.  Tline(S11) = Tline(S22)
5.  Tline(S21) = Tline(S12)

You are measuring 2 symmetric devices, so S11=S22 and S12=S21 in your measurements.

So you have 4 knowns to get 5 unknowns.  It doesn't work.

You have to make some assumptions.  A common assumption is Tline is a perfectly matched 50 ohm line.
 S11=S22=0.

That eliminates one of your unknowns and gives you 4 knowns and 4 unknowns.  That is solvable.

Now you just need to do the math correctly.  It will be horribly messy algebra.