coax probe feed patch antenna problem

i am designing a rectangular probe feed patch antenna.
My solution frequence is 10Ghz

I designed it in HFSS 10
I am new to antenna and HFSS and i dont seem to get the proper results. Please suggest what can i do to get a suitable s parameter and radiation pattern.

my results are way off the mark.I thing i am doing a mistake in feeding the patch properly.Should i change the dimensions of the patch and the coax probe.

I have tried hard but failed to detect the problem.please HELP!