RENORM with CST, HFSS
Hallo,
the direct generalized scattering paramter results for a microstrip discontinuity show return loss of approx. -20dB at DC. With increasing frequency it reaches -5dB at 30 GHz.
After deembedding the feeding lines and renormalization it shows -60dB at DC and -20dB at 30 GHz.
I would prefer to show the unnormalized S-Matrix as a result, but the much better performance after RENORM fits better to other publications, also it is only a calculated value without physical meaning from my point of view.
....
this actually depend on what you can measure :) you can measure the reflection the 50ohm coaxial line sees, which corresponds to the renormalized s parameters. You cannot measure the generalized s parameters.
A very simple example for this is a dispersive infinite transmission line, the return loss should be zero, but after renormalization it won't. And when you try to measure it, you will actually see some reflection due to the impedance variation.