SkyTower has announced that over the last few weeks it has successfully carried out a number of tests that suggest broadcasters and mobile telecommunications operators could use its stratospheric telecommunication platform commercially.
Working with NASA and the Japanese Ministry of Telecommunications, SkyTower launched a solar-powered plane called Pathfinder-Plus. After climbing to 65,000 feet above the Hawaiian island of Kauai, the unoccupied Pathfinder-Plus transmitted several hours of third-generation mobile voice, data and video service to the ground, where it was received on a standard NTT DoCoMo 3G handset.
According to Stuart Hindle, vice president of strategy and business development at SkyTower, the success of the tests shows that SkyTower's planes could complement, and in some cases supersede, satellite and terrestrial telecommunications systems.
"The airborne platform, operating above the weather and commercial air traffic, is equivalent to a 12-mile-tall tower, which means significant advantages to telecom service providers and broadcasters," Hindle said in a statement.
Because the signal is being transmitted from directly or almost directly above, the SkyTower system will cover areas that cannot receive satellite or terrestrial signals because large buildings or other obstacles are obstructing them.
According to SkyTower, which is a subsidiary of solar-powered vehicles pioneer AeroVironment, a commercial launch of the airborne services could take place in 2005.
Wireless on the wing
The upper wing of the Pathfinder-Plus plane is made up of solar panels, which generate the energy for the aircraft to remain in flight throughout the day. The plane must land at night, but SkyTower is trying to create fuel cells that would store enough energy to allow the plane to stay circling a city overnight.
Such fuel cells could enable an airplane to stay in the air for up to six months at a time, according to SkyTower.
SkyTower says that the extremely tight turning circle of the Pathfinder-Plus means that the plane stays within a small area throughout its flight--so people on the ground will not have to keep moving their receiving equipment to track it.
This suggests that SkyTower's technology is ideal for broadband fixed wireless access and digital television services, but the company says it should be of interest to 3G operators as well.
"Given the amount of money that wireless service providers have spent on spectrum licenses for both fixed and mobile applications, these SkyTower tests should be of great interest," Hindle said.
AeroVironment has been working on solar-powered plans for many years. Its projects include Helios, a solar-powered plane somewhat similar to Pathfinder-Plus. Last year Helios flew to 96,500 feet, higher than any non-rocket-powered plane had ever managed before.
