Preparing for 6G: A look at one of its promising technologies

For the average citizen, 5G may seem like the last frontier, but experts are already planning for the next phase – the sixth generation of wireless communication networks, or 6G. One of the pioneering candidate technologies for 6G networks are RISs, which are investigated in a recent study conducted with partial support from the EU-funded RISE-6G project. The research findings were published in the journal ‘Intelligent and Converged Networks’.

“Despite the massive roll-out of 5G networks worldwide, which provide higher flexibility and spectrum/energy efficiency compared to their fourth-generation counterparts,” 6G wireless networks and beyond will inevitably “require more radical communication paradigms, especially at the physical layer,” states study co-author Ruiqi Liu of ZTE Corporation, China, in a news item posted on ‘AZoSensors’. According to Liu, RISs are “among the most promising technologies that will make their way into 5G-advanced and 6G standards and eventually into future networks.”

RISs are artificial planar structures with integrated electronic circuits that can be programmed to dynamically control the incoming electromagnetic field in a wide variety of functionalities. A RIS’s ability to redirect an incoming signal to accurately reach the intended receiver, or pair it with another for a stronger connection, makes better coverage possible. Additionally, RISs are more energy efficient than previous technologies.“The incorporation of RISs in wireless networks has been recently advocated as a revolutionary means to transform any wireless signal propagation environment to a dynamically programmable one for various networking objectives,” notes Liu. In their study, the research team review the latest advances in RIS hardware architectures and the most recent developments in the modelling of RIS unit elements and RIS-empowered wireless signal propagation. They also discuss the available channel estimation approaches for RIS-empowered communications systems and the relevance of RIS technology in the latest wireless communication standards.

“Currently, the global standards of wireless communications, mainly specified by the 3rd-Generation Partnership Project (3GPP) that unites telecommunication standard development organizations to establish the mobile broadband standard, has not explicitly included RIS as a feature,” observes the researcher. “However, RIS can be evolved from the current work on network controlled repeaters and can be deployed in a standard transparent way for current networks—if it is compatible with all current designs and doesn’t rely on any new signaling.”

The study also draws attention to current and future RIS technology standardisation activities and the consequent RIS-empowered wireless networking approaches. Liu remarks: “We believe that the current standardization activities will help to mature this technology and pave way to its commercialization in the future. Currently, though, RIS is still a dynamic research topic under study, with many possible options to explore. Many key issues still need to be solved before launching RISs commercially.”

RISE-6G (Reconfigurable Intelligent Sustainable Environments for 6G Wireless Networks) is exploring innovative solutions based on the latest advances in RIS technology for the creation of intelligent, sustainable and dynamically programmable wireless environments that go well beyond 5G capabilities. “Future networks will be greener, more affordable and intelligent because of the advantages RIS can provide, so we highlighted important aspects of RIS in this paper to provide an understanding of this technology and how the wireless network will evolve towards the next generation,” the researcher concludes.

For more information, please see:

RISE-6G project website