septum polarizer

Does anybody know how to simulate a septum polarizer? I have some problems (calibration lines,impedance line, number of modes, etc) because there is no difference between RHCP and LHCP in my simulation.

Which simulator you use?

I achieved excellent results when simulating 1.2 GHz septum (4steps) polarizer in MWS.

Regards,

eirp

ON Ansoft HFSS: I have the same result (phase shit of 90°) exciting left or right input port with TE10 mode (square septum polarizer).