floquet modes
Hi,
first of all draw ur reflectarray unit cell inside an airbox. After that u must apply master/slave boundaries at the lateral faces of the airbox itself, so 2 masters and two slaves if u are using a rectangular lattice. Then, u can assign a floquet port to the airbox face opposite to the reflecting unit cell. Setting the port for such a case require the definition of just two modes, so called fundamental modes in the Floquet expansions. By using such an approach u are considering two possible orthogonal plane waves incident to your unit cell. Lattice vectors for the Floquet port must have a common origin at an arbitrary corner of the face where the port is placed. The first vector, A, must lie on one edge of that face while the vector B must lie on the orthogonal edge of the same face. Once u have defined this situation, just apply the deembedding at the port up to the cell surface. The s11 phase and amplitude is what u are looking for. Consider that u will have 2 S11s, one for the first mode and one for the second orthogonal mode. In order to understand which is the right parameter to be analyzed, visulize the port modes and choose ur desired polarization. And that's it. I hope u can manage to perform ur analysis with these information. Good Luck!
Ivan