differential mode impedance

I designed a common-mode filter with HFSS，I got the common-mode & differential-mode S parameters, and many Z parameters, but, I don't know
which is the common-mode & differential-mode impedance of the common-mode filter.
Who can help me ?

Hi,

You should look at the port field display (in the project manager tree).
Under Port Field Display, expand one of the ports, and click one of the modes.
Zoom into the waveport and look at the fields.

If the strong field is between the traces, and one of the traces has arrows from the ground and the other trace has arrows to the ground -> then this is the diff mode.
If the strong field is between the traces and the ground (both in the same direction) -> this is the common mode.

Itai

pl tell me how to assign feed to CPW structures in HFSS