From Liquid Crystal on Silicon and Liquid Crystal Reflectarray to Reconfigurable Intelligent Surfaces for Post-5G Networks

This communication aims to address the recent surge of interest in reconfigurable intelligent surfaces (RISs) among both academic and industrial communities, which has largely neglected historical developments two other underpinning technologies, i.e., liquid crystal on silicon (LCOS) reflectarray antenna (LCRA). Specifically, this focuses state art LC-RIS, highlighting unique features newly raised enabling technology for post-5G (6G) networks comparing it LCOS, operates at different frequencies is suited use cases. Drawing insights from existing knowledge LCOS LCRA, opportunities challenges are explored LC-RIS’s technical advancements enhancing coverage, capacity, energy efficiency wireless networks. In particular, development status roadmap LC-RIS China reviewed.