SoftBank Corp. Aiming to Realize Ubiquitous Connectivity by Integrating Communications on Ground and Sky

SoftBank Corp. (TOKYO: 9434) is promoting a "Ubiquitous Transformation" (UTX) for communications-an aim to create a world where people can stay connected anytime and anywhere by integrating Terrestrial Networks (TN) on the ground with Non-Terrestrial networks (NTN) in the sky, including satellites in space and base stations in the stratosphere (High Altitude Platform Station, HAPS).

Under its vision for UTX, SoftBank is seeking to overcome current communication barriers, such as disruptions during disasters and disparities in network deployments, and bring innovation to people and businesses around the world.

In this first installment of a four part series of interviews with people behind SoftBank's UTX initiative, we spoke with Masayuki Kamimura, who is working on planning, strategy development and technical implementation to realize a Ubiquitous Network.

Taking up the challenge of integrating ground- and sky-based connectivity

What do you mean by "Ubiquitous Transformation" (UTX)?

UTX is SoftBank's initiative to create a world where communication is never disrupted. This will be done by integrating ground-based terrestrial networks with non-terrestrial networks, such as stratosphere-based High Altitude Platform Station (HAPS) communication, as well as Geosynchronous Earth Orbit (GEO) and Low Earth Orbit (LEO) communication satellites. In other words, UTX refers to realizing a world where anyone can stay connected, anytime and anywhere, through a Ubiquitous Network, which will drive innovation for people and businesses.

What kind of network are you building to make UTX a reality?

We're aiming to build a three-dimensional communication network. In contrast to conventional two-dimensional networks, which are composed solely of terrestrial infrastructure, we're looking at a network configuration that includes 'altitude'-namely, the ground, the stratosphere, and space-to form a three-dimensional communication network. In other words, a three-dimensional network represents the expansion of communication infrastructure to include vertical extensions into the sky, including the stratosphere with HAPS platforms, and space with satellites.

Our aim is to create a system in which an orchestrator (an integrated control function) automatically switches between terrestrial networks on the ground-such as LTE, 5G, and eventually 6G-and non-terrestrial networks in the sky and space utilizing HAPS, GEO and LEO, to deliver stable and reliable communication services. In other words, it's about incorporating non-terrestrial networks into SoftBank's terrestrial network.

In Japan our terrestrial network has a population coverage rate close to 100%, but in terms of land area, coverage is only about 60%. We're working to build a network that covers both "altitude" and "surface area" through a multi-layered configuration, extending coverage to the remaining 40% of the uncovered land as well as maritime areas.

What are the specifics and current status of your UTX solutions?

We're planning to begin pre-commercial HAPS services in Japan in 2026. In addition to "Sunglider," a fixed-wing aircraft HAPS platform that we've been developing to date, we recently announced an investment in the U.S.-based company Sceye and the utilization of their Lighter Than Air (LTA)-type HAPS platform that uses helium for buoyancy.

For our pre-commercial service in 2026, we're planning communications services that assume a limited number of areas and users for disaster recovery purposes. From 2027 onward, in addition to offering rapid communications network restoration in times of disaster, we aim to provide services in locations where existing mobile networks have difficulty reaching, such as mountainous areas and remote islands. We're expecting our communication services provided directly from HAPS platforms will be accessible to customers using existing smartphones, including those without a satellite communications mode.

Our satellite communication services are "Eutelsat OneWeb" and "Starlink Business." Eutelsat OneWeb provides a high-speed, high-capacity, secure, and high-quality satellite communication service, while Starlink Business offers high-speed, low-latency data communications. In 2026, we're planning to offer "direct to cellular" (D2C) services that enable direct connections between satellites and smartphones.

We also plan to leverage the global IoT platform of our group company Cubic³, which develops connectivity solutions for software-defined vehicles (SDVs). Earlier this year, Cubic³ announced the world's first automotive SIM that integrates terrestrial cellular networks with non-terrestrial networks.

SoftBank entered into a strategic partnership with Cubic³ to realize Ubiquitous Networks for SDVs. In collaboration with satellite communication providers, we're aiming to commercialize seamless connectivity solutions for connected vehicles within the next few years.

UTX is now entering the implementation phase. What kinds of actual use cases can we expect to see?

Using a natural disaster as an example, imagine a scenario where a disaster occurs and ground base stations collapse, making communication impossible. In the initial response phase, satellite communication can be used. However, due to their capacity limitations, satellites can currently support text messaging, not voice communication. It often takes time to restore ground base stations, and there are additional delays caused by transportation disruptions and the need to ensure worker safety.

This is where HAPS comes into play. In normal times, they can remain on standby in the stratosphere, but in the event of a disaster, they can move over an affected area within a few hours to act as "airborne base stations," providing voice calls and data communications. The ability to flexibly switch between communication methods-satellites, HAPS and ground base stations-is a key strength of UTX.

So stratosphere-based and satellite-based communications serve different purposes?

Yes, satellites can cover wide areas at once, making them suitable for creating broad areas of network coverage. HAPS, on the other hand, are about capacity. In addition, when providing communication to customers using smartphones or feature phones that do not support satellite mode during a disaster, HAPS is an effective means of communication.

We're providing UTX solutions with an understanding of these differing technical characteristics and limitations, and working to solve our customers' issues. We believe that UTX can contribute not only in times of disaster, but also help bridge the digital divide in our everyday lives.

UTX a new and unique form of connectivity

How will our lives change with the realization of UTX?

With UTX, even during disasters, smartphones will stay connected. Online classes or remote medical care will also be possible on remote islands or deep in the mountains. Drone deliveries, autonomous driving, smart agriculture, and smart construction will become commonplace. I believe UTX can contribute to making all of that happen. Places without connectivity will disappear from the map. This is the kind of work I want to pursue through UTX.

Are similar initiatives being carried out in Japan and abroad?

The term "Ubiquitous Network" has become widespread within the telecommunications industry so many are familiar with the term. In both Japan and abroad, there are some satellite communication operators and mobile network operators that offer non-terrestrial network services. However, in Japan, we take pride in the fact that SoftBank is the only company capable of integrating terrestrial, stratospheric, and satellite networks with Cubic³'s global IoT platform, and offering all of these solutions in a single, multi-layered package.

SoftBank not only has the network capabilities to bring all of the solutions together; we also collaborate with partners like Cubic³. On a global level, that makes SoftBank a company that's uniquely positioned to take a clear path toward implementation.

Are there any other words you have for readers?

Starting in 2026, we'll gradually begin our commercial rollout of a three-dimensional communications network that covers both ground and sky.

We'll not only integrate the services of existing satellite communication operators and HAPS platforms with SoftBank's terrestrial network. Using our UTX interface, we'll also partner with other satellite communication operators and new partners to create an environment that can interconnect the different networks with flexibility.

Our ultimate goal is to eliminate all locations without communications. Working toward that goal, we're united by our slogan: "Go, Ubiquitous Transformation: welcome to the next era of unlimited connectivity." Guided by these words, we'll move forward toward social implementation, one step at a time.

(Posted on August 19, 2025)
by SoftBank News Editors