Japan’s SoftBank Corp. is putting more support behind High Altitude Platform Stations (HAPS) with the issuance of a Sustainability Bond, which is a bond that raises funds exclusively for projects that help resolve environmental and social issues.

According to SoftBank, funds raised from the unsecured HAPS bond will be used exclusively for SoftBank’s HAPS business, where it aims to provide connectivity from the stratosphere. Plans for the funds include capital expenditures, research and development, as well as business operations and other areas related to the HAPS business. The bond is to be issued during the fiscal year ending March 31, 2022.

To recap, SoftBank's HAPS are unmanned aircraft systems (UAS) flown in the stratosphere that act as airborne base stations. The UAS are designed to provide stable internet environments that deliver connectivity to mountainous areas, remote islands, developed countries and other areas and regions lacking access to traditional telecom networks.

These HAPS networks are capable of providing LTE and 5G directly to existing smartphones and other devices. Combining HAPS-based networks with terrestrial telecom networks allows network operators to realize even wider network area coverage, according to SoftBank.

In addition to providing communications for consumers, HAPS is expected to play a role in rescue efforts and network recovery when large-scale natural disasters occur on the ground.

Toward that end, SoftBank subsidiary HAPSMobile developed the “Sunglider” unmanned aircraft system that runs on solar power. Just over a year ago, HAPSMobile celebrated a stratospheric test flight of Sunglider from Spaceport America in New Mexico.

RELATED: Loon, HAPSMobile deliver LTE from fixed-wing aircraft in stratosphere

SoftBank describes its HAPS business as being in the development stage, and full-scale commercial services from SoftBank aren’t expected to start for another five or so years – at the beginning of 2027.

Other projects aimed at the stratosphere haven’t been successful. In 2018, Facebook announced it was shutting down the Aquila business, which sought to use a fleet of solar-powered aircraft to connect people in remote parts of the world. The social media giant didn’t completely abandon the high-altitude space, but said it preferred to devote its time and energy toward partnerships with other entities and on getting more spectrum allocated for such endeavors on a worldwide scale.

Project Loon, which started in Google before graduating to Alphabet, shut down at the beginning of this year, but about 200 of its patents went to SoftBank, which planned to use them to help accelerate preparations for commercial HAPS services.

RELATED: SoftBank acquires 200 HAPS patents from Loon

SoftBank and HAPSMobile also said they would use their patent portfolio to promote standardization and interoperability in the HAPS industry. In October, they announced their contribution to the ITU-R's
“HAPS Radiowave Propagation Prediction Method“ global standard. SoftBank described it as representing a “major contribution” to operators around the world aiming to deploy HAPS services.