Shaping Future 6G Networks

6G networks and services are expected to play a central role as the backbone of our future societies by tightly integrating virtual and physical spaces. Japanese governmental agencies have forged the term Society 5.0 to designate this future society that Japan should aspire to be. Following the hunting society (Society 1.0), agricultural society (Society 2.0), industrial society (Society 3.0), and information society (Society 4.0), Society 5.0 should achieve a high degree of convergence between cyberspace (virtual space) and physical space (real space). In this future Society 5.0, huge amounts of information from sensors in physical space are accumulated in cyberspace and analyzed by artificial intelligence (AI) to provide intuitive and near‐real‐time feedback to humans in physical space. This vision first drawn by science fiction authors in the early 1980s is about to become a reality. “Cyberspace… Data abstracted from the banks of every computer in the human system. Unthinkable complexity.” wrote William Gibson (who coined the term of cyberspace) in his 1984 novel Neuromancer .

The recent COVID‐19 misfortune might appear as a new step toward this Society 5.0, as we have re‐recognized the need for enhancing and upgrading information communication infrastructure to ensure the continuity of our social activities, as well as the growing blurring between virtual and real relationships. On this road, it is essential not only to promote research and development of technology but also to consider the global environmental impacts (such as carbon neutral and green recovery), the social inclusiveness so that no one will be left behind, and the ethics and social acceptability of these forthcoming technologies.

This wish for a future better and enhanced society shall be and remain the underlying foundation for designing future 6G networks. It should bond all the stakeholders engaged in research and development of next‐generation cyber infrastructure, 6G mobile network systems, to globally unite forces to define new requirements, use cases, and fundamental theories and technologies that must be realized for the next decade. These researches are also a way to progress for accomplishing the 2030 Agenda for Sustainable Development adopted by the United Nations in 2015, where one of the sustainable development goals is about building resilient infrastructure, promote inclusive and sustainable industrialization, and foster innovation.

Although it is just the very beginning of our journey for developing 6G mobile networking, we can assume that the next‐generation cyber infrastructure will bring us communications features very close to human capability, such as ultralow latency, ultra‐high capacity, ultra‐large number of connected devices, ultralow power communication, stringent security and privacy, autonomy enabled by machine learning and AI, and ultra‐coverage and extensibility including non‐terrestrial networks, underwater communication, etc.

This journey will not only be driven by the telecom industry. Many countries have allocated frequency white space to private 5G usage and made open to non‐telecommunication companies so that they can operate their own customized 5G networks. We believe that this “democratization” (i.e. making something accessible to anyone) of 5G networks will open a door to new innovations coming from the civil society as well as from industrial players. 6G will thus be the opportunity to conciliate various types of innovations: grassroots innovations coming from local players with new use cases and ad hoc solutions, radio and core layer innovations coming from Telco players, and also real‐time software innovations coming from Internet player. Besides the regular migration path from 5G to 6G promoted by telecommunication operators and vendors, there is another evolution avenue possible, from private 5G to private 6G and then to public 6G because a lot more stakeholders may participate in the game of developing custom solutions tailored for their real use cases that may be eventually distilled and adopted as viable 6G technologies to be standardized.

Along with the editors, I hope that this book serves as a navigating compass in our endeavor for developing 6G infrastructure for the next decade, by providing the insights from internationally known distinguished experts.

Akihiro Nakao

The University of Tokyo, Japan