On the Road to 6G: Visions, Requirements, Key Technologies, and Testbeds

TLDR

5G is commercially deployed, offering new services, yet it faces challenges that have spurred international research into 6G, with white papers and ITU‑R discussions outlining its vision, requirements, and open issues. This paper presents a comprehensive overview of the 6G vision, technical requirements, and application scenarios, and identifies future research directions and open challenges. It critically appraises the 6G network architecture and key technologies, and details existing testbeds and advanced verification platforms. The paper discusses lessons learned to date regarding 6G networks.

Abstract

Fifth generation (5G) mobile communication systems have entered the stage of commercial deployment, providing users with new services, improved user experiences as well as a host of novel opportunities to various industries. However, 5G still faces many challenges. To address these challenges, international industrial, academic, and standards organizations have commenced research on sixth generation (6G) wireless communication systems. A series of white papers and survey papers have been published, which aim to define 6G in terms of requirements, application scenarios, key technologies, etc. Although ITU-R has been working on the 6G vision and it is expected to reach a consensus on what 6G will be by mid-2023, the related global discussions are still wide open and the existing literature has identified numerous open issues. This paper first provides a comprehensive portrayal of the 6G vision, technical requirements, and application scenarios, covering the current common understanding of 6G. Then, a critical appraisal of the 6G network architecture and key technologies is presented. Furthermore, existing testbeds and advanced 6G verification platforms are detailed for the first time. In addition, future research directions and open challenges are identified to stimulate the on-going global debate. Finally, lessons learned to date concerning 6G networks are discussed.