alto
Due to its unique geography, Japan is an ideal testing ground for HAPS. Many of the country’s approximately 430 inhabited islands are remote, mountainous and sparsely populated, making it very expensive to connect them with terrestrial cell towers. Aalto HAPS is partnering with Japan’s largest mobile network operators, NTT DoCoMo, and telecommunications satellite operator Space Compass, who want to use Zephyr as part of their next-generation telecommunications infrastructure.
“Non-terrestrial networks have the potential to transform Japan’s communications ecosystem, addressing access to connectivity in hard-to-reach areas while supporting our nation’s response to emergencies,” Space Compass co-CEO Shigehiro Horii said in a statement. statement.
Zephyr, Auborg explains, will function like another cell tower in the NTT DoCoMo network, only it will be located high above the planet’s surface rather than near it. It will provide high-speed 5G connectivity to smartphone users without the need for special terminals that are usually needed to receive satellite internet. “For the user on the ground, there is no difference when they switch from the terrestrial network to the HAPS network,” Auborg says. “It’s exactly the same frequency and same network.”
New Mexico-based Skye, which has developed a solar-powered helium-filled airship, is also eyeing Japan for pre-commercial trials of its stratospheric connectivity service this year. The company, which launched a large-scale test of its 65-meter-long vehicle in 2025, is working with the Japanese telecom giant softbank. Like NTT DoCoMo, SoftBank is betting on HAPS to take its network to another level.
Mikael Frandsen, Skye’s founder and CEO, says his company succeeded where Loon failed by betting on the benefits offered by a more controllable airship shape, intelligent avionics and innovative batteries that power electric fans to keep the plane in place.
“Google’s Loon was groundbreaking, but they used a balloon form factor, and despite advanced algorithms – and the ability to change altitude to find desired wind directions and wind speeds – Loon’s system was dependent on favorable winds to remain over the target area, resulting in unpredictable station-seeking performance,” says Frandsen. “This required large quantities of balloons in the air for relative certainty that someone would remain in the area of operation, which was economically unviable.”
He says Skay’s airship can “point to the wind” and maintain position more effectively.
“We have significant surface area, which provides enough physical space to carry more than 250 kilograms of mass and house solar panels and batteries,” he says, “allowing Skye to maintain power through day-night cycles, and therefore remain in the area of operation while maintaining altitude.”
