It's a Bird, It's a Blimp ...

Computerworld - The higher a radio antenna, the longer its range. That's why the tops of the highest buildings in any city bristle with a porcupinelike thatch of antennas.
But no matter how high the building, range is limited by obstructions such as hills, other buildings and the curvature of the earth.
Two aerospace companies believe they've found a way to build the ultimate antenna tower, one that will eliminate obstruction problems that plague terrestrial systems. Both hope to use high-altitude aircraft or airships to provide wide geographic coverage for cellular, wide-band data and high-definition television at a fraction of the cost of satellites and without the thousands of towers required to operate a cellular telephone system.
Communications satellites eliminate the obstruction problem by positioning antennas and transmitters 22,300 miles above the earth in a geostationary orbit. But satellites are expensive and difficult, if not impossible, to repair.
The two high-altitude communications platform companies — Advanced Technologies Group (ATG) in Bedford, England, and SkyTower Inc., a subsidiary of AeroVironment Inc. in Monrovia, Calif. — both plan to use advanced, high-tech aircraft they call "stratospheric satellites." The aircraft would operate at an altitude of 12 miles (65,000 feet) and provide multimegabit wireless data service and cellular telephone service over an area ranging from 30 to 300 miles. Wider areas could be covered by launching more aircraft.
The two companies have pursued dramatically different designs. ATG will base its "tower in the sky" on a lighter-than-air platform whose design heritage goes back to World War I. But Gordon Taylor, marketing director at ATG, which is headquartered in a dirigible hangar, emphasizes that there's little comparison between the company's StratSat (for stratospheric satellite) high-tech airship and the dirigibles and blimps of yore.
The StratSat uses helium for lift — not the flammable hydrogen that destroyed the Hindenburg zeppelin at Lakehurst, N.J., in 1937 — and solar energy to power its electric motors and communications gear. It also has an auxiliary diesel engine. Since the StratSat operates at such a high altitude, it avoids the high winds and storms that led to the crash of a U.S. Navy dirigible in 1925. On-board, dual Global Positioning System (GPS) units will help keep the StatSats "on-station" above specific service areas, Taylor adds.
ATG has years of experience building blimps, including Fuji's advertising blimp, and it pioneered such technologies as "fly-by-wire" fiber-optic control systems years before airplane manufacturers did, Taylor says. This experience is being applied to the design of the StratSat airship, which is about 650 ft. long