The idea of using high altitude airships as a communications platform is not new. I wrote about the Sky Station in the May 1997, RF Current newsletter. The Sky Station never got off the ground and its Web site--www.skystation.com--is gone, but a new company based in Switzerland has an aggressive plan to begin test launches in 2007. It is also planning commercial sales in the 2008-2010 time frame.
Like Alexander Haig's Sky Station, the StratXX Holding AG High Altitude Platform Station (HAPS) would operate in the stratosphere approximately 21 km above the Earth's surface, where winds are not as strong as at other altitudes. At this height, the HAPS would be able to cover a ground area approximately 1,000 km in diameter. With such a large footprint, spot beams would be required to allow frequency reuse for most services. StratXX sees the HAPS as a suitable platform for 3G/4G wireless communications and digital broadcasting services. Communications could be provided outside the 1,000 km coverage area by linking multiple HAPS airships or through the use of satellites.
However, the use of satellites would negate one of the major benefits that a stratosphere based communications platform offers -- low latency. Anyone using a satellite Internet service for VPN access or voice over IP is familiar with the problems caused by the time it takes the signal to make it to and from a satellite. The 21 km height of the HAPS is negligible compared to the terrestrial distances it can cover, providing latency similar to that associated with fiber.
StratXX listed other potential applications including surveillance of persons, goods, and areas; monitoring; reconnaissance and intelligence; data collection and remote sensing; mapping; weather; and location services including air and maritime traffic control.
An article, "Mobile phone airship to conquer stratosphere," quoted inventor Kamal Alavi saying each airship is expected to cost no more than $32 million. The article notes that at this altitude, public exposure to RF radiation is not a problem. It also said that StratXX has a team of 50 scientists working on the first HAPS airship, which they call the "X-Station." The GPS steering system was developed by the Swiss Federal Institute of Technology. Ruag, the large Swiss aerospace company, designed the platform containing the technical equipment. The article said solar cells are currently being tested at 30 km and final preparations are underway for the launch of the first airship.
If you are interested in this technology, be sure to check out the presentation on the StratXX.com Web site. The only link to the presentation on the home page is in the upper right and corner and is easy to miss. Just click on "Presentation" and use the navigator button that appears in the lower right to move from page to page.
StratXX isn't the only company developing high altitude communications platforms. RTI and its research partners at Unitech, Applied EM, the International Communications Group and TechSphere Systems International have tested "paint-on" antennas for airships.
According to RTI, the "paint-on" antenna was tested during actual flights in the Nevada desert on an SA-60 spherical airship. The antenna and airship successfully demonstrated voice and data transmission as well as teleconferencing capabilities during the flights. David Myers, vice president of RTI's Engineering and Technology Unit said, "The successful airship test flights demonstrate exciting possibilities for 'paint-on' antenna technologies. This new technology can be used to assist with hurricane disaster relief, provide enhanced security of ports and borders, perform science observation missions and improve military communications."
The tests used a spherical airship designed using Sierra Nevada and TechSphere technology. Additional information on this project is available online.
