.matteo wrote on Jun 27^th, 2009, 12:48pm:
"RF Toolbox" is MATLAB not Simulink.
MATLAB are different from Simulink.
See documents of "RF Blockset" of Simulink.

If you have "RF Blockset", you can use s2p file easily.
Use the following three blocks.
   RF Blockset>Physical>Input/Output Ports>Input Port
   RF Blockset>Physical>Input/Output Ports>Output Port
   RF Blockset>Physical>Black Box Elements>General Passive Network

Of course, here you have to understand concept of equivalent lowpass model for RF bandpass system very correctly to use these blocks.

If you don't have "RF Blockset", create complex coefficients FIR model to express S21 as equivalent lowpass model.
Of course, also here you have to understand concept of equivalent lowpass model for RF bandpass system very correctly.

You have to understand that models of Simulink are no more than signal flow system not energy conservative system which have flow and potential, although "RF Blockset" take account of S11, S12 and S22.

.matteo wrote on Jul 1^st, 2009, 9:22am:
Not correct.
It seems you don't understand S-parameter you measured at all.

Your S-parameter is for ANT-Space-ANT.
Your concern is S21, so input and output must be terminated by 50ohm.