Convert S-parameters to different Z0

[alextang0112]

Hi guys,

I have a 4-port s-parameters measured in 50ohm. Now I would like to see what will all the matrix elements of the s-parameters look like if the termination impedance is 42.5ohm. I know that some EDA tools(like ADS) is capable of doing this job, but can anyone tell me how to convert the s-parameters step by step ? Thank you.

For example, the original s-parameters in 50ohm Z0 is,
S11r S11i S12r S12i S13r S13i S14r S14i
S21r S21i S22r S22i S23r S23i S24r S24i
S31r S31i S32r S32i S33r S33i S34r S34i
S41r S41i S42r S42i S43r S43i S44r S44i

Then what will all these 16 elements be if the termination impedance is 42.5ohm ?

Sincerely thanks.

 

[pancho_hideboo]

->[Z] for Rref=50
[Z]->[Snew] for Rref=42.5