any experiences in designing an antenna on an EBG structures

Anyone has experiences and documents in designing an antenna on an EBG structure.
I tried so many times to design a bent monopole antenna on an EBG structure but the results are not good.
And I wonder whether HFSS can simulate the effect of EBG structures on performance (gain, return loss...) of an antenna.
Please give me some suggestions.
Thank you.

ı read from the paper it says monopole antenna not good for EBG dipol could be usefull