SoftBank targets commercial HAPS service from 2027
SoftBank has successfully tested a High Altitude Platform Station, or HAPS, that provided mobile communications from the stratosphere directly to ordinary smartphones on the ground in Japan. The company said the trial enabled two-way communication using a smartphone without a special satellite handset, and that it is aiming to begin commercial services in Japan from 2027 onward.
HAPS systems use aircraft or airship-like platforms equipped with communications equipment. These platforms remain in the stratosphere at an altitude of approximately 20 kilometers, creating a wide-area communications network from above. Because HAPS can use radio frequencies compatible with terrestrial mobile networks, customers may be able to connect with existing smartphones rather than purchasing dedicated satellite communication devices.
Testing conducted over Kochi Prefecture
For the latest demonstration, an airship-shaped HAPS developed by U.S.-based Sceye traveled more than 15,000 kilometers from New Mexico before remaining above waters near Cape Muroto in Kochi Prefecture, on Shikoku. The platform carried a base station equivalent to a 4G LTE network and connected it to SoftBank’s core network.
During the test, users successfully made voice calls, exchanged messages, accessed social media, watched videos and held video calls through regular smartphones. SoftBank also tested emergency communications, including earthquake early-warning notifications, tsunami alerts and emergency calls to Japan’s Coast Guard through the 118 service. The company said it achieved communications performance comparable to a terrestrial network while limiting radio interference with ground-based mobile stations.
Potential role in disasters and underserved areas
For Japan, a country frequently affected by earthquakes, typhoons, landslides and other natural disasters, HAPS could offer an important alternative when ground infrastructure is damaged or inaccessible. The technology could help restore communications after a major disaster by covering affected areas from above, potentially supporting residents, emergency workers and public authorities.
SoftBank also envisions using HAPS to expand mobile coverage in mountainous regions, remote islands and offshore areas. These locations can be difficult or expensive to serve with conventional ground stations, while Japan’s geography makes reliable communications especially important for communities, transportation routes and maritime operations.
Drone control and lower-latency data processing
The trial went beyond smartphone connectivity. SoftBank successfully used the HAPS network to remotely control drones, including testing autonomous flight and video transmission. Such capabilities could support disaster assessment, infrastructure inspections, logistics and search-and-rescue operations in areas where terrestrial networks are unavailable.
The company also tested edge computing by installing a server on the HAPS platform and processing data in the stratosphere. According to SoftBank, this reduced communications latency by more than 40 percent compared with processing data through a cloud system. Lower latency could be valuable for drone operations and other applications requiring rapid data exchange.
Commercial deployment will still depend on further technical, regulatory and operational preparations. However, the successful connection of standard smartphones marks a significant step for Japan’s efforts to combine mobile networks, aviation technology and space-related communications. If the plan advances as intended, HAPS could complement—not replace—ground infrastructure and provide a flexible communications layer above Japan.
