RF Choke Impedance from S-Parameters

Can you give us an example of a part you're looking at, and your frequency of interest? What are you working on?

1. I believe that if you measured an RF choke, it is just a 2 terminal, 1 port device. In that case, you only have one s parameter.
2. The s parameter is a complex number.
3. It may be given in POLAR form as a magnitude and an angle.
4. Or it could be a complex number with real and imaginary parts e.g. 1 + j1.
5. If the measurements were done at several frequencies, you may have a table with a frequency and two other values on each line. Hopefully, the titles show if it is polar or complex and indicate the units
6. Whether polar or complex, the values could be normalized to the test instrument resistance - usually 50 ohms. For example, an impedance 1 + j1 would mean 50 ohms resistance (the 1 part) in series with 50 ohms inductive (the j1 part).
7. One needs to know if the tabulated value is impedance (amps per volt) or admittance (volts per amp)!
   

Please give an example of the parameter values you get and state the instrument standard resistance. The nominal (Makers Data Sheet) value of the impedance and the test frequency on the data sheet would help a lot - to compare with your test values - hopefully you made a measurement at the makers standard test frequency.

Try here to convert S-parameters to Z-parameters...

http://en.wikipedia.org/wiki/Impedance_parameters#Relation_to_S-parameters

Thanks guys i found what i needed in some microwave engineering books, thanks for your help anyway, cheers Raul Velasquez