How to simulate single/coupled ring resonators in HFSS?

At present, I have been trying to simulate single/coupled open-loop resonators in HFSS. But I encounter several problems on how to set ports on the coupled open-loop resonators and input/output tapped single open-loop resonator in HFSS for EM simulation.

For coupled resonators, when I try to find a relationship between spacing "s" and coupling coefficient "k" by simulating them in HFSS, should I add extra tapped input/output line onto the side that is opposite to the coupled side and then set a de-embedding length which is equal to its length so as to get rid of the parasitic effect it adds? or is there some other better way to do it? If the former way is ok, where should I connect input/output port onto the resonator? Is the input/output location related with the offset "d" between two coupled resonators when they are not positioned on same horizontal line?

Besides, for the tapped single input/output resonator, how long should I set for the tapped input/output line? Is there any requirement or guidance on that?

I am really in trouble with those EM simulation sets for open-loop resonatorsin HFSS. Would anyone please do me this favor and help me out? Thanks.

Hi godsound !

It's a bit difficult to understand what you mean. Please attach your hfss project if possible.

Usually the length of the input waveguide shoud be enough to attenuate all below cut-off high-order modes exited at the junction with the resonator.

The resonator itself is characterized with certain parameters: Complex Eigens, Stored Energy, Surface and volume losses (internal Q),
coupling with connected waveguides (external Q) and shunt-impeadance (R/Q - interaction with a passing charge).
What are you looking for ?