Skip to main content

NTT Docomo and Airbus Demonstrate Zephyr HAPS Wireless Broadband Connectivity

NTT Docomo and Airbus have demonstrated the ability to use Airbus's solar-powered Zephyr High Altitude Platform Station (HAPS) to deliver future wireless broadband connectivity. The trial took place in the United States in August, when the Zephyr S aircraft undertook approx. 18-day stratospheric flights to test various capabilities. We have covered many of the topics here, see related blog posts link at the bottom.

A press release said:

Carrying an onboard radio transmitter, the Zephyr S provided an agile datalink during a stratospheric flight to simulate future direct-to-device connectivity. Test data was captured at different altitudes and at different times of day and night, focusing on assessing how connectivity is affected in the stratosphere by factors including weather conditions, different elevation angles and aircraft flight patterns.

Tests included various bandwidths to simulate direct-to-device service from the HAPS to end users using low, nominal and high throughput. The demonstration confirmed the viability and versatility of the 2GHz spectrum for HAPS-based services and also the use of a narrow (450MHz) band to provide connectivity in a range of up to 140km.

The measurement and analysis of the propagation of radio waves transmitted from Zephyr demonstrated the feasibility of stratospheric communications to devices such as smartphones. Based on the results of this experiment, Airbus and NTT DOCOMO aims to provide communication services to mountainous areas, remote islands, and maritime areas where radio waves are difficult to reach.

"DOCOMO believes that HAPS will be a promising solution for coverage expansion in 5G evolution and 6G," said Takehiro Nakamura, General Manager of DOCOMO's 6G-IOWN Promotion Department. "In this measurement experiment, we were able to demonstrate the effectiveness of HAPS, especially for direct communication to smartphones, through long-term propagation measurements using actual HAPS equipment. Based on these results, we would like to further study the practical application of HAPS in 5G evolution and 6G with Airbus."

As part of efforts to further advance 5G and prepare for 6G, "coverage expansion" to expand communication networks to any location, including air and sea, is being studied worldwide. To achieve this, non-terrestrial network (NTN) technology is expected to be used. In addition to coverage of the air and sea, stratospheric HAPS networking will be useful for disaster preparedness and many industrial use cases, for example, to increase communication capacity in densely populated areas such as event venues, and remotely controlling heavy equipment at construction sites.

The test data will be used to inform future LTE direct-to-device services that are expected to be provided via the Airbus Zephyr HAPS solution.

A recent article (Oct 2021) in NTT Docomo Technical Journal on 'Research on NTN Technology for 5G evolution & 6G' has details on some of the things NTT Docomo is trying to achieve with NTN solutions. It's available here.

I especially liked this comparison of HAPS-mounted stations.

(click on image to enlarge)

Related Posts

Comments

Popular posts from this blog

Highlights from XGMF's Conference to Advance Millimetre Wave Technology

On April 1, 2024, two of Japan's leading connectivity organizations—the 5G Mobile Promotion Forum (5GMF) and the Beyond 5G Promotion Consortium (B5GPC)—joined forces to create the XG Mobile Promotion Forum ( XGMF ). This merger symbolizes a pivotal step in accelerating the adoption of next-generation wireless technologies. In May 2024, XGMF's Millimeter Wave Promotion Ad Hoc (Millimeter Wave AH) hosted the International Workshop on Millimeter Wave Dissemination for 5G. This event aimed to foster the adoption of millimeter wave (mmWave) technology in Japan and beyond, drawing an audience of approximately 200 attendees and broadcasting in both English and Japanese. The workshop featured opening remarks by Mr. Naohiko Ogiwara, Director of the Radio Department, Telecommunications Infrastructure Bureau, Ministry of Internal Affairs and Communications (MIC). Key speakers included: Mr. Takanori Mashiko (MIC, slides ) Mr. Sam Gielges (Qualcomm, online - no slides) Mr. Christopher Pric...

IEEE 802.11bn Ultra High Reliability (UHR), a.k.a. Wi-Fi 8

Back in 2020 we looked at the introductory post of Wi-Fi 7 which was followed up by a more detailed post in Feb 2022. We are now following on with an introductory post on the next generation Wi-Fi.  A new paper on arXiv explores the journey towards IEEE 802.11bn Ultra High Reliability (UHR), the amendment that will form the basis of Wi-Fi 8. Quoting selected items from the paper  below: After providing an overview of the nearly completed Wi-Fi 7 standard, we present new use cases calling for further Wi-Fi evolution. We also outline current standardization, certification, and spectrum allocation activities, sharing updates from the newly formed UHR Study Group. We then introduce the disruptive new features envisioned for Wi-Fi 8 and discuss the associated research challenges. Among those, we focus on access point coordination and demonstrate that it could build upon 802.11be multi-link operation to make Ultra High Reliability a reality in Wi-Fi 8. The IEEE 802.11bn UHR: Whose ...

Testing, Refining, and Improving Stratospheric Connectivity: NTT Docomo’s HAPS Trials

At MWC 2025, NTT Docomo highlighted its latest initiatives under the NTT Group's "NTT C89" space-business strategy, such as mobile-connectivity services using unmanned vehicles, or high-altitude platform stations (HAPS), that fly in the stratosphere for days or months, using relays to provide mobile connectivity in mountainous and remote areas, including at sea and in the sky. A presentation on NTT C89 Aerospace Business Strategy is available here while a presentation on NTT DOCOMO's Non-Terrestrial Network (NTN) for Extreme Coverage Extension is available here . Stratospheric connectivity, enabled by High Altitude Platform Stations (HAPS), is emerging as a key solution for extending mobile coverage to remote and underserved areas. However, ensuring that these airborne platforms can provide stable, high-quality connectivity requires extensive testing and refinement. At MWC 2025, NTT Docomo showcased its progress in this domain, highlighting multiple real-world trials...