On the Design of Reconfigurable Passive Skins towards a Smart EM Environment for Next Generation Wireless Communications - Challenges, Solutions, and Trends

Reconfigurable passive electromagnetic skins (RP-EMSs) are considered one of the fundamental technologies to implement the "Smart EM Environment" paradigm in next generation wireless communications. Despite their popularity and the already demonstrated successful applications of such a technology, several challenges still need to be addressed concerning the design, optimization, control, and implementation of cost-effective and efficient RP-EMSs. A review of the most recent advances and trends in this framework will be discussed in this work.