Learning Forum

[daniel.richardson]

When modeling lumped ports in HFSS, is renormalization equivalent to re-simulation?

For context, I have been modeling antennas. I am curious if when I change the port impedance in the model from say 50 ohms to 1 ohm, if I need to re-simulate with that new port impedance, or if I can just renormalize to 1 ohm to get the correct response. My personal intuition is that you do in fact need to re-simulate because the port is a physical boundary condition in the model, and thus this new impedances changes the field profiles. My intuition is that using renormalization as a substitute for re-simulation can get you close as an approximation if the field profiles are not substantially altered between changes in impedance. The opposing idea being that you can just simulate your antenna 1 time with say 50 ohms, and then you can renormalize (without ever re-simulating) to any impedance you want and have the correct S parameters for any port impedance value.

 Thanks!