Ah, I see why we couldn't understand your question.
You don't know how to work in HFSS. So, I recommend you first try to follow basic tutorials to get familiar with the editor. (Autodesk 3D studio/3DMAX experience would be very helpful as well)
It is pointless to ask here questions about metamaterials, while you don't know how to simulate simple resonator.
BTW. There are some tutorials exactly for basic SRR structures can be found at ANSOFT of.site.
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And I should poit it, that SRRs are NOT UWB. Of course you can operate in the whole Brillouin zone, but it will have very large refraction index and impedance dispersion in the band. And plasmonic wires are very lossy as well. You should turn to DR based 3D structures.