Boundaries and Excitations

Hello Everybody,

I am very new learner of HFSS. I started modeling an simple antenna. And I got problem to get the correct result after simulation.
I just want to report the result return loss and realized gain. But it showed completely wrong. I know something about setting up model such as Boundaries Excitations, ... like i said I am just new learner.
Attached is my HFSS file ( very small. Do not worry )
Could anybody point out where I was wrong ( see my HFSS file )

Thank you very much in advance. I really appreciate.
blueray08