set port in cst

Hi everyone,
I have a problem. I am simulating a FSS cell in CST Studio and I want to calculate the reflection coefficient in a frequency range with a plane wave (TEM mode). I am using a waveguide, but I am not sure which mode I am exciting with a waveguide. Any of you can you tell me how to excite a TEM mode with a waveguide port.
Thanks in advance,
David

Hi,
You should set a waveguide simulator with two opposite magnetic walls parallel to the electric field and the other two walls as electric walls. Then, put waveguide ports where you want the plane wave to incide.
Regards,
Iaia

Hi,
I not sure, what is FSS cell, but so you have TEM mode, you probably use coax waveguide as source. In set of port you can set number of mode, the TE or TEM will be set automaticly. For exemple, for rectangular waveguide the port will in TE mode automaticly, you can set number of mode.