2
Table of Contents
1. Introduction
................................................................................................................ 2
2. Direction of Evolution “5G Evolution and 6G” ...................................................... 3
2.1. Considerations for 5G evolution ...................................................................... 3
2.2. Considerations for 6G ........................................................................................ 5
3. Requirements and Use Cases ............................................................................... 7
3.1. Extreme-high-speed and high-capacity communications ............................ 7
3.2. Extreme coverage extension ............................................................................ 8
3.3. Extreme-low power consumption and cost reduction
................................... 8
3.4. Extreme-low latency........................................................................................... 9
3.5. Extreme-reliable communication ..................................................................... 9
3.6. Extreme-massive connectivity & sensing ..................................................... 10
4. Technological Study Areas ................................................................................... 10
4.1. New network topology ..................................................................................... 11
4.2. Coverage extension including non-terrestrial network ............................... 12
4.3. Frequency extension and improved spectrum utilization ........................... 13
4.4. Further advancement of wireless transmission technologies ................... 13
4.5. Enhancement for URLLC and industrial IoT networks ............................... 14
4.6. Expanded integration of variable wireless technologies ............................ 15
4.7. Multi-functionalization and AI for everywhere in mobile network .............. 15
5. Conclusion ............................................................................................................... 16
References ...................................................................................................................... 16
1. Introduction
Since the Nippon Telegraph and Telephone Public Corporation (NTT) initiated the world’s first
c
ellular mobile communication service in December 1979, the technology of mobile
communications has continued to develop every decade, evolving to new generation systems.
With the progress of technology, services have continued to evolve. From the first generation (1G)
to the second generation (2G), voice calls were the main means of communication, and simple
e-mail was possible. However, from the third generation (3G), data communications such as
“i-mode” and multimedia information such as photos, music, and video could be communicated
using mobile devices. From the fourth generation (4G), smartphones have been explosively
popularized by high-speed communication technology exceeding 100 Mbps using the Long Term
Evolution (LTE), and a wide variety of multimedia communication services have appeared. 4G
technology continues to evolve in the form of LTE-Advanced, and has now reached a maximum
communication speed close to 1 Gbps. NTT DOCOMO plans to initiate services based on the fifth
generation (5G) mobile communication system [1-1], which is a more technologically advanced
system, in the spring of 2020.
5G is expected to provide new value as a basic technology supporting future industry and
society, along with artificial intelligence (AI) and the Internet of Things (IoT), as well as further
upgrading of the multimedia communication services with its technical features such as high
speed, high capacity, low latency, and massive connectivity. As shown in Fig. 1-1, the mobile
communication system has been evolving technically every decade, while the services of mobile
communications have changed greatly in cycles of approximately 20 years. Therefore, the “Third
Wave” initiated by 5G is expected to become a larger wave through 5G evolution and the sixth
generation (6G) technology, and will support industry and society in the 2030s.
This white paper describes NTT DOCOMO’s current technical prospects for 5G evolution and
6G. Chapter 2 discusses the direction of future technological evolution from the viewpoints of 5G
