hi deer
for this antenna better u use SMA and for simulation u should use wave port in hfss11
and for more information u can read this book
Broadband Planar Antennas Design and Applications by Zhi Ning Chen and Michael Y. W. Chia
in chapter 5 u can find this antenna and in chapter 3 u can find feeding by microstrip
hi
create a hole in u antenna ground page with r=1.6 and then design a pin in center of it with r=0.6 and the height of pin h=.5mm(1mm) + H which H the height of u ground page and u pin u been .5mm(1mm) upper than u ground like the fig u attach