ANTENNA SIMULATION SOFTWARE : PLEASE HELP

Hello I am trying to simulate a patch antanna array with different types of feeds:
Binomial,Dolph-Tschebyscheb etc.
I need to calculate directivity,bandwidth etc.
Please suggest me a good software.
I need to have a control on feed.
I have CST MWS but do not know how to give the different feeds.
In my case each of the patch antennas of the array will have different types of feed.
E.g. say the feeds will differ in amplitude or phase.
Please help