problems with the coordinate systems in hfss!

when i simulate a patch antenna (please see the attachment),i find the 3D polar radiation pattern is not solid .I guess it is because the x-y plane is over the ground plane as it is computed .

my question is if we choose different coordinate systems before simulation, will the results be different ? if not ,can we choose different coordinate systems to observe the results in the post processing?

Best regards!

Hi,
I do not think it is a coordinate system problem, please check what are your settings for the infinite sphere in the radiation section(check phi, theta values), leave the default of change them to span all the area phi (0 to 360) and theta from (0 to 180), I believe that you set theta from 0 to 90, this is why you have this problem.
hoping this will solve your problem, by the way nice fractal antenna.

if this is not the problem, add your file to check it.

Regards,