help in hfss ..........

hi all,
can any one tell me where the problem in this file ? the result s11 not as the result in paper

the file:
circular-patch-anter.rar

the paper :

Antar Compact Disc Monopole Antennas for Current and Future (UWB) - Copy (2).pdf

Kindly upload the Picture of your schematic & simulation result. since not everyone has HFSS installed.
Not receiving required S11 would probably because of improper input matching. what about other S parameters (S21 & S22) are they fine?

thank you for help me...
i'am new here ... so i need time to learn ^_^
this is picture of my design , the parameter taken from paper


in the paper the s11 vs frequency (figure .4) not like my result, there are more than 30 db different , and i don't know why ?
i try to google and search from more than one month....