Space-air-ground integrated network (SAGIN) for 6G: Requirements, architecture and challenges

• Published in: China communications Vol. 19; no. 2; pp. 90 - 108
• Main Authors: Cui, Huanxi, Zhang, Jun, Geng, Yuhui, Xiao, Zhenyu, Sun, Tao, Zhang, Ning, Liu, Jiajia, Wu, Qihui, Cao, Xianbin
• Format: Journal Article
• Language: English
• Published: China Institute of Communications 01.02.2022; School of Electronic and Information Engineering,Beijing Key Laboratory for Network-Based Cooperative Air application Management,Beihang University,Beijing 100191,China%Advanced Research Institute of Multidisciplinary Science,Beijing Institute of Technology,Beijing 100081,China%China Mobile Research Institute,Beijing 100053,China%Department of Electrical and Computer Engineering,University of Windsor,ON,Canada,N9B 3P4%National Engineering Laboratory for Integrated Aero-Space-Ground-Ocean Big Data Application Technology,the School of Cybersecurity,Northwestern Polytechnical University,Xi'an,Shaanxi,710072,China%College of Electronics and Information Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210007,China
• Subjects: 5G mobile communication; 6G mobile communication; Control systems; Industrial Internet of Things; Logic gates; Network architecture; NTN; Protocols; SAGIN; DT; AI; 6G; Network ar-chitecture; NTN; SAGIN
• ISSN: 1673-5447
• DOI: 10.23919/JCC.2022.02.008

As the fifth-generation (5G) mobile communication network may not meet the requirements of emerging technologies and applications, including ubiquitous coverage, industrial internet of things (IIoT), ubiquitous artificial intelligence (AI), digital twins (DT), etc., this paper aims to explore a novel space-air-ground integrated network (SAGIN) architecture to support these new requirements for the sixth-generation (6G) mobile communication network in a flexible, low-latency and efficient manner. Specifically, we first review the evolution of the mobile communication network, followed by the application and technology requirements of 6G. Then the current 5G non-terrestrial network (NTN) architecture in supporting the new requirements is deeply analyzed. After that, we proposes a new flexible, low-latency and flat SAGIN architecture, and presents corresponding use cases. Finally, the future research directions are discussed.