free rf simulation
It can handle anytype of S2p files. I tried using the De-embedding function of ADS (Agilent) but I was not able to get any results. I had two different files from two different vendors, i.e the S2p files have nothing to do with each other, i.e. different number of samples, different number of data points, different frequency range, and it was still able to get very accurate results. Also, one of the data files had a non-linear sampling. I guess that is why I was not able to use ADS for it. You can try the software for a couple of weeks, I guess.
Yara