How can I simulate the helical Antenna in CST?

My final project is about the design of the helical antenna. 2.45GHz, and to search the Wifi.
I have designed the helix and reflector but I am in trouble to simulate.
Is there anyone know how to simulate the helical antenna in cst?
Thanks a lot

Examples -> MWS -> Integral Equation -> Helix -> Helix_I_Wire.cst
Unfortunately, this is second-hand information. The example path was only mentioned in a meeting.

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As I understand it, you put a port over the end of the coaxial input, exactly as in the tutorial examples for coaxial stuff.

I should mention that the one in the picture was used to feed a dish reflector, which reverses the expected sense of the helix rotation. LHCP becomes RHCP after a reflection.

Thanks for your suggestion
I used CST Microwave software to design the Helical Antenna. I made the coaxial at the end of helix but it can't simulate. it show " Domain calculation is completely filled with PEC please check background material and layer properties". I have changed the background material but it is not working as well. Do you have any idea about this problem?