Modelling a 3-port resonator cavity in ADS using s2p files

Hi, not sure if this is the right place for this thread, but it looked the most appropriate to me. Forgive me if I'm wrong.

I have a 3-port microwave resonator cavity which I have measured using a VNA. I've used ADS before but my knowledge is very limited - I was hoping someone might be able to help!

I have 3 s2p files and I'd like to use them to model the cavity in ADS so that I can a) plot graphs using the data; Smith charts etc. and b) use the model when I come to design a PA.

So how should I go about doing this?

Thanks,

Mike.