Boundary Methods in HFSS for Metasurfaces: Differences and Port Placement?

[Kudo Holmes]

Greetings, I hope you're all doing well.
I am currently working on a project involving the use of HFSS for the boundaries of the unit cell of a meta-surface. I have noticed that some researchers use ‘master’ and ‘slave’ along with ‘floquet ports’ for the boundaries of the unit cell. On the other hand, some use ‘perfect H’ and ‘perfect E’ along with ‘wave ports’.
Could anyone explain the difference between these two methods?
Additionally, I have observed that sometimes the ports are placed at the front and back of the unit cell, and sometimes on the sides (left and right or top and bottom).
Could anyone provide insights on this as well?
Any help would be greatly appreciated. Thank you in advance!

 

[PlanarMetamaterials]

PerfectE/H pairs can only be used to simulate an array of symmetric structures under normal incidence. Floquet ports long with M/S (now known as Primary/Secondary) boundaries gives one the option of simulating the structure under illumination at any angle in 3D space, as well as decomposing the response into a series of higher-order diffraction modes.

Ports on the top/bottom of the cell are for examining transmission/reflection through the plane of the cell; ports on the sides are used for examining transmission/reflections along the plane of the cell.