General Outline of 5G Field Trials
Marubashi Hirohito

Assistant Director
New-Generation Mobile Communications OfficeLand Mobile Division, Radio Department
Telecommunications Bureau
Ministry of Internal Affairs and Communications

1. The start of commercial 5G services

2. 5G Field Trials

In March 2020, mobile phone carriers began offeringcommercial 5G (5th generation mobile communication system)
services. The three main benefits of 5G are that it enables ultrahigh speed communication, has ultra-low latency, and supports
multiple simultaneous connections. It is expected that thesebenefits will enable the development of completely new services,such as allowing people to view realistic live images of remotelocations like tourist spots and sports stadiums from various
different angles.
In particular, 5G is the only technology that supports ultralow latency and multiple simultaneous connections. The former
allows real-time communication to be implemented with low
delays, while the latter makes it possible to connect multiple
IoT devices at the same time (Figure 1). Applications that takeadvantage of these features are being considered for use invarious industrial fields, such as automatic farm managementin agriculture, smart factory applications in the manufacturingindustry, and the remote control of construction machinery in theconstruction industry.

The Ministry of Internal Affairs and Communications(MIC) has promoted efforts aimed at the realization of 5G,
including research and development, international cooperationand standardization, allocation of frequencies to 5G, and theformulation of technical standards. As a part of this, with theaim of creating new markets through the realization of 5G, athree-year program of 5G Comprehensive Demonstration Tests(hereinafter referred to as “5G Field Trials”) was performed fromFY2017 through FY2019 with the participation of stakeholders
from various fields related to the use of 5G technology (Figure 2).
In this article, we look back on the achievements of this program.
In the first year (FY2017), mobile phone operators proactively
selected multiple themes and locations in which 5G is envisaged to
be used in practice, and performed technical studies relating to thebenefits of 5G with regard to speed, latency and connectivity.
In FY2018, 5G technical verification and performance
evaluation tests were conducted for various use cases basedon eight issues identified by the ICT Infrastructure Regional
Development Strategy Study Group of the Ministry of Internal■ Figure 1: What is the 5th generation mobile communication system (5G)?

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■ Figure 2: Implementation status of 5G Field Trials■ Figure 3: Outline of 5G Field Trials (FY2019)

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■ Figure 4: 5G Field Trials around Japan (FY2019)

Affairs and Communications. The ministry also organized a5G Utilization Idea Contest with the aim of soliciting unique
ideas from around Japan that provide solutions to various local
problems. A total of 785 entries were received during Octoberand November 2018. In December of the same year, primary
screening was performed by the ministry’s Regional Bureaus ofTelecommunications and Offices of Telecommunications (11locations nationwide), and in January 2019, the leading proposals
selected in primary screening were entered into a contest(secondary screening) held at the Ministry of Internal Affairs andCommunications. In the secondary screening, presentations weremade by each proposer, and as a result of examination by a panelof judges, the overall grand prize was awarded to an entry from
Shikoku, which proposed exploiting the characteristics of 5G toprovide a better working environment, safer working conditions,and the transfer of skills from highly skilled workers (proposer:
Distributed Processing Systems Laboratory, Ehime University
Graduate School of Science and Engineering). Other proposals
also received awards, including the 5G Characteristic Utilization
Award and the Regional Problem-Solving Award.
In FY2019, based on the results of previous technicalverification and the results of the 5G Utilization Idea Contest,
we conducted demonstrations at 23 locations nationwide withan emphasis on models that use 5G to help solve local issues(Figures 3, 4).
The implementation status of the 5G Field Trials in FY2019 isintroduced below.
For example, based on Ehime University’s prize-winningidea mentioned above, NTT DOCOMO entered into a joint

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verification trial aimed at ensuring the safety of crane operations
through the use of high-definition images at a shipyard in Imabari
City, Ehime Prefecture. To operate a shipyard crane more safely,
ultra-fast high-capacity 5G communication was used to transmit
high-definition video images of a crane’s blind spot to the crane
operator’s cabin, thereby eliminating the blind spot and providing
a safe work environment where the crane can be operated safely
while checking this video.
KDDI Corporation and others demonstrated a remote control
and integrated construction management system for construction
machinery in Iga City, Mie Prefecture. This uses 5G’s ultralow latency communication to resolve worker shortages andobserve working conditions in real time by using remote control
of construction machinery and management of construction workat a site where roadbuilding at a dam construction site was beingsimulated.
Also, a group including a company called Wireless City
Planning demonstrated the provision of safety management for
tunnel workers in Akaigawa Village, Hokkaido. Using 5G’s
support for multiple simultaneous connections, they made it
possible to detect anomalies inside the tunnel with environment
sensors during tunnel engineering works, and by performing
remote operation of construction machinery in the event of adisaster or accident, they were able to ensure the safety of workers.
The Ministry of Internal Affairs and Communications has
also been working on publicity and advertising related to 5G,including holding the 5G International Symposium 2020 inFebruary 2020 in order to publicize the results of the 5G FieldTrials in 2019 in Japan and around the world.

3. The deployment and evolution of 5G
To make 5G available throughout Japan, it will be necessary to
set up as many 5G base stations as possible. Here, we introduce thefrequency allocations for 5G.
On April 10, 2019, the Ministry of Internal Affairs andCommunications allocated frequencies for 5G to four mobilephone carriers (planning and accreditation of specific basestations). In the 3.7 and 4.5 GHz bands, NTT DOCOMO
was allocated 200 MHz of bandwidth (3600–3700 MHz and4500–4600 MHz), KDDI Corporation and Okinawa CellularTelephone Co., Ltd. were allocated 200 MHz (3700–3800 MHzand 4000–4100 MHz), 100 MHz (3900–4000 MHz) was
allocated to SoftBank Corp., and 100 MHz (3800–3900 MHz)was allocated to Rakuten Mobile Inc. In the 28 GHz band, NTT
DOCOMO was allocated 400 MHz of bandwidth (27.4–27.8GHz), KDDI Corporation and Okinawa Cellular Telephone Co.,
Ltd. were allocated 400 MHz (27.8–28.2 GHz), SoftBank Corp.
was allocated 400 MHz (29.1–29.5 GHz), and Rakuten Mobile
Inc. was allocated 400 MHz (27.0–27.4 GHz).
To promote early deployment, the Ministry of Internal Affairs
and Communications obliged each mobile phone operator tobegin offering 5G services in all prefectures within two years
when allocating frequencies for 5G in April 2019. To promote thebroad expansion of 5G services across the entire country, these
deployment guidelines divided the whole of Japan into a grid of
10 km squares, and evaluated the performance of 5G providersin terms of the number of squares in which they had deployed
5G base stations with advanced characteristics. According to thepreparation plans of each mobile phone operator, 5G will havebeen deployed across 98% of the country by the end of FY2023, bywhich time 5G networks are expected to be deployed throughout
the whole of Japan, including rural areas. 5G is expected to be
rapidly deployed nationwide as a core infrastructure for the 21stcentury, which is indispensable for regional development.

4. Local 5G
Ministry of Internal Affairs and Communications is
promoting an initiative called Local 5G, whereby organizations
such as local companies and local governments can flexibly deploy
and use 5G hotspots in their respective buildings and premises
according to the individual needs of the region and industry(Figure 5).
In FY2020, to enable local businesses and other organizations
to solve regional issues through the use of Local 5G, Local 5G
technical verification tests were performed in use cases assuming
a diverse variety of Local 5G base station installation locations
and usage environments, and through these verification tests,
development demonstrations are being performed in which
Local 5G is used to construct regional problem-solving models.
In FY2020, demonstrations are being performed to address
issues in the fields of primary industries (agriculture, fisheries),
factories, infrastructure/mobility, tourism/culture/sports, disasterprevention/crime prevention, work style reform, and medicine/
healthcare.
Through these efforts, the Ministry of Internal Affairs andCommunications will continue to make a concerted effort topromote the development of 5G infrastructure and the promotionof 5G applications including Local 5G.
Finally, in order to solve regional issues with 5G, in addition
to the knowledge of telecommunications carriers and equipmentvendors, it is also essential to consider the viewpoints and ideasof 5G end-users. It is hoped that knowledge gained from the5G Field Trials will be put to good use and that 5G will become
more widespread and popular through the cooperation of various
stakeholders including telecommunications carriers, equipmentvendors, and end-users.

■ Figure 5: Overview of Local 5G

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