Recent Progress in Reconfigurable and Intelligent Metasurfaces: A Comprehensive Review of Tuning Mechanisms, Hardware Designs, and Applications

• Published in: Advanced science Vol. 9; no. 33; pp. e2203747 - n/a
• Main Authors: Saifullah, Yasir, He, Yejun, Boag, Amir, Yang, Guo‐Min, Xu, Feng
• Format: Journal Article
• Language: English
• Published: Weinheim John Wiley & Sons, Inc 01-11-2022; Wiley
• Subjects: Copyright; Design; Field programmable gate arrays; Graphene; intelligent metasurfaces; Internet of Things; machine learning; Phase transitions; Principles; reconfigurable intelligent surfaces; simultaneous transmission and reflection; sixth‐generation; space–time modulation; tunable; Unmanned aerial vehicles; Wireless communications; Wireless networks
• ISSN: 2198-3844; 2198-3844
• DOI: 10.1002/advs.202203747

Intelligent metasurfaces have gained significant importance in recent years due to their ability to dynamically manipulate electromagnetic (EM) waves. Their multifunctional characteristics, realized by incorporating active elements into the metasurface designs, have huge potential in numerous novel devices and exciting applications. In this article, recent progress in the field of intelligent metasurfaces are reviewed, focusing particularly on tuning mechanisms, hardware designs, and applications. Reconfigurable and programmable metasurfaces, classified as space gradient, time modulated, and space–time modulated metasurfaces, are discussed. Then, reconfigurable intelligent surfaces (RISs) that can alter their wireless environments, and are considered as a promising technology for sixth‐generation communication networks, are explored. Next, the recent progress made in simultaneously transmitting and reflecting reconfigurable intelligent surfaces (STAR‐RISs) that can achieve full‐space EM wave control are summarized. Finally, the perspective on the challenges and future directions of intelligent metasurfaces are presented.
This review presents the recent progress of intelligent metasurfaces, focusing on tuning mechanisms, hardware designs, and applications. The authors discuss the reconfigurable and programmable metasurfaces, classified as space‐gradient, time‐modulated, and space–time modulated metasurfaces. Furthermore, the emerging research direction of reconfigurable intelligent surfaces are demonstrated. Finally, the challenges and future directions of intelligent metasurfaces are presented.