RFID antenna design and port allocation using CST

Hello everyone!
I am currently trying to design a UHF RFID tag to resonate at 867MHz for my project work. Problem is that I am not very good with CST and it is giving me serious problems. I have already designed my antenna but I am having problems with placing my ports. can some one please tell me how to do this? the antenna type is a slotted loop antenna. I would be very grateful if anyone can help me because i am already running out of time for my project I will also be grateful if someone can refer me to a useful material since there is no specific simulation example by cst for rfid antenna design Thank you.

Checkout the EDABoard group:
RFID Technologies
I have already posted many links concerning both RFID Antenna Design and Circuit Design, with more being posted daily.
Ciao

hi
pls attach u simulation file