Almost ten years have passed since SoftBank Corp. (TOKYO: 9434) launched its High Altitude Platform Station (HAPS) initiative. Often described as "flying base stations," HAPS is designed to provide mobile connectivity from the stratosphere. Since 2017, SoftBank has steadily advanced the commercialization of HAPS through research and development, as well as international standardization activities. This summer, SoftBank plans to conduct its first HAPS flight operation and connectivity test over Japan.
During a webinar held on July 23, 2026, Masayuki Kamimura, a Senior Director at SoftBank’s Ubiquitous Network Planning Division, provided details on how SoftBank is preparing for this milestone.
How HAPS differs from “SoftBank Starlink Direct”
Kamimura explained the basics of HAPS, noting that the technology provides direct-to-device mobile communications from the stratosphere, where atmospheric conditions are relatively stable. HAPS use cases include maintaining communications during disasters, bridging the digital divide and providing connectivity for drones and other aerial mobility services.
SoftBank is pursuing its vision to realize a Ubiquitous Transformation (UTX) that envisions a world where connectivity is truly ubiquitous. To this end, SoftBank is working to integrate non-terrestrial networks (NTN), including HAPS and satellite communications, with terrestrial mobile networks. “Our aim with UTX is to provide optimal connectivity for different use cases—whether on land, at sea, or in the air,” Kamimura explained.
Given the recent launch of SoftBank Starlink Direct on April 10, 2026, Kamimura highlighted how HAPS is different. SoftBank Starlink Direct is primarily designed to provide low- to medium-capacity communications from space to areas that have traditionally lacked mobile coverage, such as mountainous regions, remote islands and offshore locations.
“By contrast, HAPS is designed to deliver high-quality, high-capacity communications comparable to terrestrial mobile networks,” Kamimura said. “We also aim to enable the rapid restoration of communications following disasters through HAPS.”
Encouraging results from historic 12-day stratospheric flight
Kamimura then gave an update on preparations being made for the HAPS flight operation and connectivity test in Japan scheduled for this summer.
He noted that SoftBank’s partner Sceye, Inc., a New Mexico, U.S.-based company that develops lighter-than-air (LTA*)-type HAPS platforms, successfully achieved a key milestone when its platform departed Roswell, New Mexico, on March 25, and completed all scheduled test items during a flight that lasted over 12 days. Sceye’s HAPS platform travelled over 10,300 kilometers in the stratosphere before completing its mission in international waters off the coast of Brazil.
- *
LTA: A HAPS platform that remains airborne by utilizing buoyancy, being lighter than air.
Kamimura described the test flight results as very encouraging. The platform's ability to maintain its position despite wind conditions was confirmed, and its power management cycle was verified, demonstrating the reliability needed for long-term operations.
Kamimura also noted that SoftBank successfully completed end-to-end communications testing by connecting communication equipment for installation on the HAPS platform with SoftBank's core network. Using a standard SoftBank smartphone, the company verified voice, SMS and data communications across the entire communications path, achieving another important milestone ahead of this summer's trial.
SoftBank installs ground gateway to prepare for HAPS connectivity test in Japan
To prepare for the upcoming trial, Kamimura said that in mid-July SoftBank conducted installation checks on a ground gateway facility in Kochi Prefecture on Japan’s Shikoku Island, located on Japan’s Pacific coast. The gateway will communicate with Sceye’s HAPS platform once it arrives in Japan.
The ground gateway’s role is to connect the airborne HAPS platform to SoftBank's core network, and it is designed to automatically track the HAPS platform throughout its flight, ensuring stable communications. The ground gateway can also be deployed to disaster-affected areas, where it links the HAPS platform with SoftBank's core network.
Sceye’s HAPS platform will be launched from its hangar in Roswell, New Mexico, and then cross the Pacific Ocean to Japan. During the flight, the platform will be controlled via satellite communications. Once it arrives over Japan, it will connect to SoftBank’s ground gateway, after which communications trials using smartphones will be conducted within a simulated disaster area.
“We plan to conduct the trial service in areas that simulate large-scale disasters,” Kamimura said. “Potential locations include Kochi Prefecture, as well as parts of the Kinki, Kyushu and Tohoku regions.”
The HAPS trial service will focus on three main objectives:
- Confirm that the HAPS platform can achieve performance levels already demonstrated in the United States under Japan's environmental and meteorological conditions.
- Verify that HAPS can provide voice calls, SMS and data communications from an altitude of approximately 20 kilometers with a level of quality comparable to terrestrial mobile networks.
- Evaluate the level of radio interference, if any, that HAPS communications may have on surrounding terrestrial mobile networks.
Kamimura concluded that the platform’s flight performance, end-to-end communications testing and ground gateway installation preparation have all been successfully completed, leaving SoftBank fully prepared for this summer's HAPS trial service.
Contributing to advanced mobility and AI-enabled services with HAPS
Looking beyond the trial, Kamimura said SoftBank plans to begin commercial HAPS services in 2027 or later, and pursue additional use cases in the years ahead.
“Our vision is to expand today's 2D communications infrastructure into a 3D communication network extending into space,” he said. “To achieve this, we’ll connect multiple HAPS platforms with Low Earth Orbit (LEO) satellites using optical wireless communications, creating a multi-layered, 3D telecommunications network. Ultimately, we believe this network will support future innovations such as advanced mobility and AI-enabled services, while contributing to a broader digital transformation across society.”
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(Posted on July 31, 2026)
by SoftBank News Editors
