Japanese firm Rakuten Mobile has begun joint research with the University of Tokyo Graduate School of Engineering into IoT coverage using low Earth orbit (LEO) satellites.

The research is one of the R&D themes of the Beyond 5G R&D Promotion Project, which the National Institute of Information & Communications Technology (NICT) recently publicly invited applications for proposals.

The two organisations will use satellite communications to expand geographical coverage to 100% and enable long distance communications with existing NB-IoT and IoT devices with the aim of achieving IoT ultra coverage.

In the R&D, Rakuten Mobile and the University of Tokyo will leverage their expertise in satellite communications technology and NB-IoT to build an IoT network using LEO satellite communications and establish new use cases for IoT services using NB-IoT and LTE devices.

NB-IoT is a telecommunications standard for low power IoT devices that uses a very narrow band of spectrum. With NB-IoT, small amounts of data can be sent at infrequent intervals, making the standard suitable for IoT services that require low power consumption, such as smart meters and sensors.

By building an NB-IoT and LTE network using satellites, it should become possible to provide low-cost IoT services for various industries in locations that would typically be out of network coverage, such as mountainous areas, remote islands or on the sea.

The R&D aims to construct a satellite communications network that can collect data directly from IoT sensors, using LEO satellites to achieve 100% geographical coverage. R&D will be carried out in three areas:

• Construction of an LTE satellite communications network;
• Stabilisation and optimisation of LTE satellite communications, development and deployment of NB-IoT software for satellites; and
• Investigation of use cases and trials of IoT ultra coverage.

The research started last month and is planned to continue until the end of March 2025.

Through the R&D, Rakuten Mobile aims to enhance its satellite communications network to provide a more convenient service to its customers and contribute to the development of telecommunications technologies in Japan.

Rakuten Mobile is collaborating with AST SpaceMobile to build a satellite-based communications network using LEO satellites. With a space-based mobile broadband network, the two companies aim to provide mobile service to areas that would typically be out of coverage. Rakuten Group has invested in AST SpaceMobile.