Meshing Frequency used in simulating various frequency ranges of single antenna

hi

I m simulating an adaptive antenna designed using IE3D simulator.
I need to analyse the characteristics of the designed antenna for various frequency range(0.7-1GHZ),(1.5-2.2GHZ),(3.5-4GHz),(5-6GHZ) indiviually.

Should i use common meshing frequency for all frequency ranges when i simulate each range?
for (e.g) when i simulate (0.7-1GHz) range ,which meshing frequency i should use 2GHZ or 7GHZ(highest frequency of antenna)?

What meshing frequency i should use when i want to simulate the entire frequency range(0.7-6GHZ)?

thanks,