Recent Advances on Multi-Scale Wave Manipulation through Reconfigurable Intelligent Surfaces

The vision of Smart ElectroMagnetic Environment (SEME) has emerged in the last few years as a fundamental approach for the development of next generation wireless systems capable of delivering the required quality-of-service in comparison with current-generation architectures [1]–[5]. In fact, SEME aims at addressing the fundamental challenges arising in wireless communications and sensing by fixed propagation environments, which are traditionally considered an uncontrollable component that can only be compensated for by using increasingly sophisticated transmission/reception techniques as well as more expensive designs / higher power levels [1]–[5]. More in detail, SEME is based on a revolutionary approach to wireless system design in which the wave propagation and its interactions with existing “obstacles” can be “manipulated” to properly adapt the resulting end-to-end electromagnetic scenario to the designer’s needs and the system-level requirements and performance goals.