Why don't you "just a little bit" look at ADS documentation?? The phase noise simulation technique is well explained there.In addition to, there is a sample circuit to develop yourself.
Also, there are many sources out of Agilent in somewhere even in elektroda..
Researching something in somewhere is not a bad way..
Grig the zap file is too large (6MEG) so please see the files included in networks directory of my project. The schematic I'm interested in is ring_Isource. Hope do not need more files to perform the PN simulation. Regards,