two wire line feeding in HFSS

hello,
need urgent help! how can I feed a two wire line in hfss?
I need to evaluate the G.
thanks

use lumped port between wire lines, from radiation insert far field radiation sphere and in the far field reports you should be able to get the gain, if that's what you mean by G.

Additional recommendation for you, the lumped port's impedance should be defined properly. For example, an opened two-wire line is feed with a 300 Ω lumped port.
regards!