What Is 5G, the Next Generation Wireless System?5G Launch Eve: Rapid Preparations from Use Case Verification to Network Construction

In October 2018, the world's first 5G service began in the US. The first operator is US-based Verizon, which developed Verizon 5G Home, a home Internet service that employs 5G technologies; it launched commercial service in four areas: Houston, Indianapolis, Los Angeles, and Sacramento.

The Verizon 5G Home service provides residences with a fast wireless Internet environment via wireless access lines that combine the existing wired network with a fast wireless network on the millimeter-wave frequency band. The service features a maximum speed of 940 Mbps.

However, despite the "5G" name, the service is not for mobile devices (e.g., smartphones and tablets). As the word "home" suggests, this Internet access service is simply for residences; home devices connect to the Internet through a dedicated home appliance installed in the residence. Verizon will launch 5G service for smartphones in 2019.

Image from a video that introduces the Verizon 5G Home wireless Internet service (source: Verizon)

The technologies used in Verizon 5G Home do not conform to the international standards established by standards organizations, such as the ITU Radiocommunication Sector (ITU-R) and the 3rd Generation Partnership Project (3GPP). Rather, the service is based on unique specifications created at the Verizon 5G Technology Forum (V5GTF) in collaboration with several 5G device vendors, including Sweden-based Ericsson. The V5GTF specifications are not international standards and the only practical use that they have achieved is fast wireless access. Nevertheless, this realization of commercial 5G service enabled by combining several manufacturers' devices indicates that commercialization of 5G is shifting from competing to launch the first service toward competing to create unique services.

Completion of the First Version of an International Standard Based on New Wireless Technologies

International 5G standards are undergoing a process in which the 3GPP industry group vigorously discusses the formation of specifications, and then the outputs are approved by ITU-R, an international standards organization. Multiple next-generation mobile environments will be realized with 5G. Many use cases have been created, and efforts to achieve performance that meets the requirements of each use case are underway. Another important task is to facilitate a smooth transition from the current 4G environment to a 5G environment. These reasons have resulted in an approach to 5G standardization that involves specification expansion in several stages to achieve full implementation.

The first 5G standard that 3GPP prepared is called Release 15, which was completed in June 2018. Two major specifications were discussed for Release 15. One is NSA 5G NR, which was completed in December 2017. The other is SA 5G NR, which was completed in June 2018.

The difference between the specifications is whether or not an existing 4G system is used for communications control. This difference is denoted by "NSA" and "SA" at the start of the names. "NSA" stands for "Non-StandAlone," which indicates that the specification alone cannot realize a 5G system; rather, a 4G system is required to set it up. On the other hand, "SA" stands for StandAlone; this specification realizes a 5G system by itself; thus, no 4G system is necessary. Both specifications have "NR" at the end of their names, which is short for "New Radio," indicating that they use a new wireless system that differs from 4G in order to achieve unprecedented communications capabilities. The two specifications discussed for Release 15 are both NR, meaning that they can achieve communications capabilities that exceed those of 4G's with new wireless technologies.

In general, it takes between 18 months to 2 years from the completion of a standard to the launch of services based on said standard, so international standards-compliant 5G services that use the new NR wireless technology will be announced worldwide in 2019.

Domestic 5G Demo Service to Launch in Autumn 2019, Production Deployment in 2020

In Japan, the government and carriers are preparing to launch 5G services in 2020. In December 2018, the Ministry of Internal Affairs and Communications (MIC) announced policies on allocating frequencies to 5G carriers and opening base stations, and publicized a schedule for 5G service commercialization in Japan. The schedule states that frequencies for 5G services will be allocated by March 2019, a pre-service that doubles as a 5G demo will launch in autumn 2019, and the production service will be deployed in 2020.

How 5G service areas will be expanded and 5G services will be developed in Japan can be inferred from MIC's perspective on allocating frequencies to carriers. For evaluating 4G and earlier standards, population coverage was used as a metric because the aim was to make the service available to as many users as possible.

With regard to the allocation of 5G frequencies, MIC has set forth two new roles for 5G service. The first is to make it available not only as a means of communication for users but also as network infrastructure to connect IoT devices. The second is to help solve regional issues and to create business opportunities. MIC has defined specific priority items, namely 1) the feasibility of nationwide deployment, 2) early deployment in regions beyond Tokyo, and 3) securing of service diversity. This policy will lead carriers that offer 5G services to expand areas and develop services with a focus on the three items above.