Reconfigurable Intelligent Surfaces Enabling 6G Wireless Communication Systems: Use Cases and Technical Considerations

Reconfigurable intelligent surfaces are rapidly emerging as candidate technology to support massive connectivity in the envisioned 6G wireless networks. By proactively reconfiguring the propagation space into a smart, programmable, and truly controllable entity via an array of inexpensive passive reflecting elements, a robust improvement in the spectrum and/or energy efficiency (EE) of wireless communication systems can be realized. This paper presents state-of-the-art solutions for some critical aspects of RIS-empowered wireless communication systems. In particular, an exposition on the fundamentals of RIS technology, including its structure and operation, competitive advantages over existing frameworks, system models, and potential use cases in wireless communication systems are broached. Last, a few open research issues and key takeaway lessons are highlighted.