With all the hype about 2.5G and 3G wireless networks, it’s easy to forget a major shortcoming that GSM and CDMA share—a lack of rural coverage. With approximately 80 percent of the U.S. population living on only 10 percent of the land, wireless carriers don’t have much incentive to build hundreds of new towers to cover sparsely populated areas. But many industries rely on coverage outside of cities to keep tabs on equipment as well as keep in touch with remote workers.
That’s why a company called Space Data has developed plans for cost-effective, ubiquitous cellular coverage using cellular repeaters strapped to weather balloons. With one balloon Space Data claims to be able to cover as much ground as 250 cellular towers—at about one-quarter the cost. The company started a pilot program last November with an oil company in Texas to wirelessly transmit equipment data, such as flow rates, temperatures and pressures along pipelines. Rural industries have often turned to CDPD wireless networks for this type of transmission, but with CDPD networks becoming obsolete, Space Data is counting on these end-users to come running for a new solution.
The idea of using weather balloons as cellular repeaters isn’t new, but it only recently became feasible thanks to lighter equipment. Jerry Knoblach, CEO of Chandler, Ariz.-based Space Data, cites that Moore’s Law, the theory that data density doubles every 18 months, still holds true and is evident in executing what has been a six-year project for Space Data.
FAA regulations require commercial aircraft to withstand the impact from an 8-pound bird without damage to the plane. So Space Data’s requirements were to shrink the size of the cellular repeaters to less than 6 pounds while increasing battery life. Current battery life of the Skysites, the company’s branded, ultra-light repeater/GPS units, hovers around 24 hours. Typical weather balloons rise to 100,000 feet and then burst. Space Data needed balloons to reach 100,000 feet and remain aloft long enough to create a stable platform. At 100,000 feet a repeater can reach an area with a diameter of about 360 miles, where the average tower only covers about 24 miles.
“Balloons are launched every 12 hours, and they move about 30 miles an hour,” Knoblach explains. “So by launching every 12 hours we can provide continuous coverage to one piece of land mass with multiple balloons. That gives us redundancy in the constellation.”
And the repeaters are reusable. Weather balloon equipment has mailing labels attached. If found, the hope is that good Samaritans will mail the device back to its owner. Skysites will work the same way. Knoblach claims that about 20 percent of weather system devices are returned.
Knoblach figures only 70 launch sites would be necessary to cover the entire U.S. Although Space Data is not planning to replace coverage in metropolitan areas, that doesn’t mean the forward-thinking Knoblach is not crunching the numbers. “If you were to put up towers that covered the major metropolitan areas, you might put up 5,000 towers to cover 20 percent of the land mass. You’d pay $1,000 a month to lease each tower so that’s $60 million a year just for tower leases, before you buy any transmission equipment.
“For our system to cover the whole U.S. requires 70 launch sites, launching twice a day, 365 days a year. That ends up being approximately 50,000 launches per year, but each launch is only $300. It ends up only costing $15 million a year.”
Because the system is being built to be compatible with existing GSM and CDMA networks, the idea is to sell the service to carriers. “We have a letter of intent from a national carrier,” says Knoblach, “so the goal there is a national carrier could buy the service from us, marry it with their tower-based coverage and then sell it on to their customers as an upgrade for better coverage.”
According to Knoblach the pilot program in Texas is going very well, though the oil company was not willing to release its name.