Need Help regarding How to use PIN DIODE in CST CST Studio Suite 2011 software..!!!

I am designing the Fractral Antenna using PIN Diode. For that I am using CST Studio Suite 2011 software. But my problem is that I don't know how to use PIN Diode in CST.

So please my request is please give me any idea or step by step demo project or Steps so that I will refer that.Please

Thanks In advance...!!! :)