Problem to find S21 as function of frequency for different incident angles

Hi,
I am using HFSS for the Unitcell (with 3 dielectric layers),
I wants to find S21 as function of frequency for different incident angles in floquet port.
Could you suggest me how to change the incident angle of plane wave in floquet port.
help me if possible.

Thanks
Dev

This tutorials explains how to do that.

http://www0.egr.uh.edu/courses/Ece/E...et%20ports.pdf