How to find the radius of probe for prob fed patch antenna in IE3D

hello everyone,I need some help on how to find out what should be the probe radius for a 50 ohm feed in IE3D.For conventional calculation i need to specify both the inner and the outer radius of the coax. But in IE3D i can specify only the inner radius.

I suggest u donnot try to model a complete coax in IE3D. It would be not only tedious but also unreliable. You can just use the strip model of the probe feed to simulate the antenna impedance. If the antenna impedance is adjusted to the desired 50 ohm, the combination of the antenna and the coax feed in the real world should work OK.

I'm trying to do the same in HFSS for 50ohm matching, I have a coax fed patch antenna (should resonate at 3.15 GHz) - please find my design attached:

Patch_Coax_Ed01.zip

You will find all my design variable in the project (L, W, Xf, Yf, etc...)

- How do I adjust the Ri (inner radius, pec) Ro (outer radius, vacuum)?
- the coaxial feed length under the ground

Appreciating your guidance...