Dual Band Microstrip Patch Antenna HFSS

Hello to everyone, ,I am a ms student and new at forums. I have designed dual band(2.4 ghz and 5.8 ghz) wifi antenna and simulated it using HFSS. I have attached the project file and would be happy if anyone checked it whether everything is ok or not. Specially, i am worry about gain issue. Thanx alot

Hi.
I checked your design.
at first this warning appears:
[warning] Warning - Boundary 'Rad1' and Boundary 'PerfE1' overlap.
but no problem,with modify dimensions of air box this warning will be removed.
you have 2 resonant freq with acceptable shift and you should know that FR4 can not give high gain because it is a lossy material.
Good Luck

Thank you fereshteh, yes there is a warning about radiation boundary but i dont care that much.

dear belbimas,
i am also working on dual band patch antennas for wifi and wlan aplications.. i am interested and want to study your designed antenna. can you please share the technical details/report of this antenna? i shall be very thankful to you..