A parametric and macroscopic model for bi-lateral metasurfaces.

The thesis project introduces a macroscopic bilateral modeling methodology for Reconfigurable Intelligent Surfaces (RIS), capable of simulating diverse scenarios, encompassing both transmissive and bilaterally reradiating RIS. Expanding on recent research, the approach relies on a comprehensive power balance at the RIS surface, considering several parameters to accommodate desired and parasitic reradiation modes on both sides of the surface, as well as accounting for diffuse scattering and dissipation. The surface effect is described using a spatial modulation coefficient that embodies the wavefront transformation of each reradiation mode, including phase and amplitude modulation. The proposed model is then integrated with a Huygens-based field calculation method to assess its efficacy in different cases. After a definition of the RIS and topologies in Chapter 1, we move on to the description of the microscopic and macroscopic models. Chapter 3 focuses on the study model by describing the modification of the source model. In chapter 4, the results obtained from Matlab simulations are proposed (the Matlab code is found in Appendix 1) from the simple reflection-only and refraction-only cases up to the bilateral case with losses. Finally, in chapter 5 the conclusions are presented.