Reflection coefficient analysis of a TEM-Excited reflectarray unit cell using quality factors

In this paper, an approach to extract the reflection coefficient of reflectarray unit cells is developed using the quality (Q) factors. To obtain the radiation Q factor, an approach based on full-wave simulations is employed, while the other Q factors are derived theoretically. The accuracy of the approach is verified by comparing the presented theory with full-wave simulations. The proposed method helps simplify the reflectarray unit cell design and provides useful insight into the underlying physics.