I'm using both 3D and schematic parts of CST Studio Suite. In the 3D simulation I have a port for measurement purposes, and am exciting using a plane wave. I'm measuring the voltage across the port for a range of frequencies.

In the schematic view, I have setup a very simple circuit which is intended to re-produce what is measured on the port in the 3D part (once I have proved this I will move on to more complex designs) however so far I am unable to reproduce the same spectrum. I have tried a simple probe directly across the differential port, I have tried adding a resistor with the same resistance as the 3D port in series and in parallel, but none of these attempts have allowed me to re-produce the result in see in the 3D mode port.

Please can you advise on how to do this, as it should be very simple?