There’s no shortage of public interest in the growth of new ‘mega-constellations’ of Low Earth Orbit (LEO) satellites from the likes of Elon Musk (Starlink), Jeff Bezos (Kuiper) and Telesat of Canada.
However, there’s plenty of other aerial activity taking place somewhat closer to the ground in the shape of high-altitude balloons and airships. These, generically termed ‘high altitude platforms’ (HAPs) are making headlines, whether from Google-backed Project Loon or any of the other dozen or more concepts
The holy grail they are all seeking is connectivity with customers and users below. A report from Northern Sky Research (NSR) says there are about 18 different projects targeting the communications market, for defence and intelligence as well as commercial markets. The logic is that a high-altitude balloon, or even a highly durable and very high-flying aircraft, can ‘see’ a large city or region.
“HAPs have been proposed as a quickly deployable, long-endurance potential alternative/complement to satellite connectivity, for both fixed broadband communications as well as connectivity links between mobile and core networks for backhaul. These applications are seen as crucial to enable broadband communications in remote regions, particularly in mountainous, coastal and desert areas,” said NSR.
NSR admitted there are significant challenges to overcome if they are to become commercially viable in the global broadband connectivity market. “Prime amongst the challenges is costs: in projects like Loon, while the cost of a high-altitude balloon for communications is low in comparison to an airship or a LEO satellite, balloons are limited in capabilities in terms of platform reusability and coverage area and are not ideal for wide area communications. In addition to this, the maintenance of such a network has its own challenges, driving the OPEX higher. High altitude balloons have had their fair share of mishaps in recent years, and such accidents could dent the reputation and viability of promising high-altitude applications.”
There are also challenges as far a bandwidth is concerned. A drive from the HAPSmobile organisation is asking for the existing 2 MHz band to be expanded. “American telecom company Sprint filed a request to test the stability and reliability of a HAPs-based LTE network in 1.9 GHz and 2.5 GHz. Such an expansion could allow operators the flexibility that will be imperative in implementing a HAPs based mobile broadband communications system,” said NSR.
Google’s Project Loon topped 1 million hours in the sky earlier this year and has been testing a service in Kenya. Its balloons have also been active over disaster areas, and in October was testing signals over Belize.