how to feed the microstrip antenna with a CPW feeding

hello
i m new to hfss and i dont know how to feed the antenna with CPw feeding.
as i know, in CPW feeding the ground plane is use to be above the sustrate but i m confused because then patch is also above the substrate so if we put the ground plane above the substrate then how i will assign the ground plane as ground and how will i differentiate between the ground and the patch because they both are already above the substrate.

regards
vishal.

there is no field under the gnd plane, so just place a waveport from gnd plane up to a certain height above the patch. the substrate should be in between the gnd plane and the patch.

i m not agree with you, as i know in CPW feeding ground plane is above the substrate and we use lumped port in CPW