Satellites expand comm possibilities, but even the sky has limits

Satellites expand comm possibilities, but even the sky has limits

Communications, monitoring and tracking from space are integrated into government operations

By John Edwards

Special to GCN

NASA and the Defense Department aren't the only federal agencies pushing into the frontiers of space.



Over the past several years, a variety of satellite technologies have become vital communications tools for virtually all branches of the government, said Scott Sacknoff, president of the International Space Business Council, a space industry trade group in Arlington, Va.

'From disaster planning and relief, weather forecasting and agricultural monitoring to air traffic control or the surveillance of potential drug traffickers, the use of space for communications, monitoring and tracking has become integrated into the overall fabric of government operations,' Sacknoff said.

According to ISBC, space industry revenue'virtually all of it derived from telecommunications'reached about $97.6 billion last year.

The range of satellite systems is made up of three categories: geostationary Earth orbit (GEO), medium Earth orbit (MEO) and low Earth orbit (LEO) satellites. 'Each of these satellite technologies is geared toward a specific type of application,' Sacknoff said. 'Each has its advantages and drawbacks.'

LEO satellites

Orbiting 500 to 600 miles above the Earth, LEO satellites are close enough to work with a range of handheld devices, including phones and pagers. LEO systems consist of constellations of satellites that hand off communications in the manner of cellular antennas, providing virtually global coverage.

The most famous'and infamous'LEO system is Iridium LLC of Washington, a satellite telephone venture backed by Motorola Inc. The 66-satellite system was launched with great fanfare in 1998. But high handset and service prices hurt its business.

The company last year filed for Chapter 11 bankruptcy protection, and it has cut its prices for federal customers.

'Iridium's problems were numerous and spanned business, technical and marketing issues, but an entire industry should not be defined by the problems of one firm,' Sacknoff said.

Despite Iridium's woes, Sacknoff predicted the market eventually will turn around and that satellite phones will be-come vital tools for agencies that work in remote areas around the world. 'The market for satellite-based voice telephones is a significant market, considering that app-roximately 80 percent of the world's population does not have access to a telephone,' he said.

A pending Iridium competitor, Globalstar LP of San Jose, Calif., could revive the satellite phone market, said George Morgan, executive director of the Space and Wireless Business Center at Virginia Polytechnic Institute and State University. 'Globalstar is working on a system that will be a lot cheaper to put up,' he said.

The system uses less expensive handsets, plus 48 satellites compared with Iridium's 66. 'The charges passed along to customers will be a lot lower,' Morgan said. Globalstar service is to begin this year.

While satellite phone services struggle to find their bearings, LEO-based data networks could emerge with a bright future. SkyBridge LP of Bethesda, Md., for example, is developing an 80-satellite LEO venture that will bring broadband data service to even the most remote parts of the world.

'This could be a big help to government agencies operating in places that lack adequate terrestrial-based networks,' Morgan said. Service is set to start in about two years.

MEO satellites

MEO satellites orbit at about 6,000 miles above the Earth. The technology's advantage is that the higher altitude allows a satellite to cover more territory. Because a MEO system uses one-half to one-third the number of satellites of a LEO network, the technology is less expensive to deploy, which can translate into cheaper service rates.

On the downside, MEO phones, pagers and other devices'not to mention the satellites themselves'need larger antennas and more powerful transmitters than their LEO counterparts.

The leading MEO player is ICO Global Communications of London, a satellite phone service provider that, like Iridium, also fell into bankruptcy last year. But a fresh opportunity for ICO may exist in providing medium-rate data services to Internet users.

The 10 ICO satellites can deliver 64-Kbps data transmissions to Internet users worldwide without the need for major modifications. Service is to begin this year.

GEO satellites

Stationed at fixed orbital positions of 22,282 miles, GEO satellites are widely used for television and radio broadcasting and to provide broadband data links to phone carriers.

But distracting half-second delays'the result of the long round trip from Earth and back'limits the technology's value as a satellite telephone medium.

Minidish GEO-based data services, such as DirecPC from Hughes Electronics Corp. of El Segundo, Calif., provide high-speed Internet access to users in areas not served by Integrated Services Digital Network, cable modem or digital subscriber line links.

'With the rise of LEO and MEO, GEO has become a less important communications medium for personal users,' Morgan said. 'But LEO, and to a lesser extent MEO, are definitely the satellite markets of the moment.'

John Edwards is an information technology writer in Gilbert, Ariz.

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