Constructing 4 port S-Parameter from Multiple 2-port S-parameter Measurement

Hi all,

I have a 4-port device to be measured using 2-port NA. The other 2-port are terminated with 50Ohm load during the 2-port S-parameter measurement (total of 6 combinations). Does anybody have experience in constructing the 4-port S-parameter from the measurement data?.

Thanks

I think that the small reflections at the 50Ohms additional terminations are not calibrated by the 2-port NA and this is going to affect the obtained 4-port-S-Parameters. But anyway, mi feeling is that if you don't require very high accuracy, the measurement should fine.

from 4-ports S-paras, you can convert it to mixing-mode S-paras for differential 4 ports.

So you 1st need to measure 4 times 2 ports S-paras, I guess ADS can combine them to 4 ports S-paras. If you need differential 4 ports S-paras, you need further calculate.