Reconfigurable Intelligent Surfaces for Doppler Effect and Multipath Fading Mitigation

Extensive research has already started on 6G and beyond wireless technologies due to the envisioned new use-cases potential requirements for future networks. Although a plethora of modern physical layer solutions have been introduced in last few decades, it is undeniable that level saturation reached terms available spectrum, adapted modulation/coding accordingly maximum capacity. Within this context, communications through reconfigurable intelligent surfaces (RISs), which enable novel effective functionalities including wave absorption, tuneable anomalous reflection, reflection phase modification, appear as candidate overcome inherent drawbacks legacy systems. The core idea RISs transformation uncontrollable random propagation environment into communication system entity plays an active role forwarding information. In paper, well-known multipath fading phenomenon revisited mobile systems, unique are from perspective RISs. feasibility eliminating or mitigating effect stemming movement receivers also investigated by utilizing It shown rapid fluctuations received signal strength Doppler can be effectively reduced using real-time proven totally eliminated when all reflectors coated with RISs, while even significantly reduce spread well deep fades general environments several interacting objects.