State of Mobile Network Evolution

Mobile communications is a rapidly evolving field that encompasses various technologies, applications, and services. The main drivers of this evolution are the increasing demand for high-speed data, low-latency connectivity, ubiquitous coverage, and enhanced user experience. This white paper builds upon our previous work, “Mobile Communications Towards 2030” which was issued in November 2022 and summarizes new national and regional initiatives on 6G, along with exploring three promising technological building blocks: Full Duplex, Joint Communication and Sensing (JCAS), and Intelligent Surfaces. Chapter 1 provides an overview and update of the following national and regional initiatives: NSF Resilient & Intelligent NextG Systems (RINGS) in the U.S., TETRA in Canada, ATIS NGA in North America, as well as activities in China, Japan, Europe (Hexa X and Hexa X II, Germany, Finland), and Korea. Recent noteworthy events are additionally described, including the CHIPS and Science Act, the National Science Foundation (NSF) and National Security Council (NSC) workshop on 6G and the NSC document “principles of 6G”, the U.S. “national standards strategy for critical and emerging technology” approach, and the U.S.-EU Trade and Technology Council (TTC) and its 6G expert workshop. Chapter 2 discusses Full Duplex, beginning with static and dynamic Time Division Duplex (TDD) and introduces the first step of Sub-Band Full Duplex (SBFD) using non-overlapping uplink and downlink sub-bands at the base station. It covers the evolution of duplex mode at the base station and wireless devices, design goals and challenges, technology enablers and enhancement areas, as well as the 3GPP study on duplex evolution in 5G-Advanced and the path to 6G. Chapter 3 explores JCAS, which extends the network capability from “listen-and-talk” to “see-and-feel” and enables the network to leverage its resources and support new services. The section covers motivation, use cases and applications, as well as the evolution of positioning, joint communications and sensing, design goals and challenges, and technology enablers and enhancement areas. Finally, Chapter 4 examines intelligent surfaces, which are used to manipulate the propagation environment and improve the effective wireless channel between the transmitter and receiver. The section covers motivation, use cases, a comparison of intelligent surfaces with existing topology solutions, and addresses design goals and challenges, and technology enablers for intelligent surfaces.