The sky is going to be so crowded with low earth orbit satellites that we soon won’t be able to see out to the stars following the announcement yesterday that Bill Gates and Craig McCaw are to join forces to invest a sizable amount of their personal fortunes in what they dub a satellite-based global Internet. They have formed Teledesic Corp to build and operate the satellite network, and put the investment required at some $9,000m; Gates, whose fortune derives from his holding of Microsoft Corp shares – he still has some 40%, and McCaw, who will be exceedingly wealthy once AT&T Co has completed the deal to buy control of McCaw Cellular Communications Inc, will each hold 30% of Teledesic. The venture faces competition from two similar initiatives, the Iridium Inc effort headed by Motorola Inc, and the competing Project 21 system planned by Inmarsat, the International Maritime Satellite Organisation. The other current owners of Teledesic are McCaw Cellular Communications itself with 28%, and Kinship Ventures II, a Los Angeles venture-capital fund run by Edward Tuck, who founded the Magellan global-positioning satellite system, 10%. McCaw and Gates have each committed only a couple of million dollars so far to the project, and most of the money is intended to come from manufacturers and governments that will actually build and run the system. According to the Wall Street Journal, the Teledesic application filed with the US Federal Communications Commission for allocation of spectrum bandwidth for the system shows that the idea borrows heavily from the now-defunct Strategic Defense Initiative and its brilliant pebbles concept: the system would use 840 refrigerator-sized satellites – an order of magnitude more than Iridium’s system. The network would provide videoconferencing, interactive multimedia, and a variety of real-time data and speech channels, opening for business in 2001. The satellites would operate in the little-used very high frequency Ka-band – 20GHz to 30GHz and each satellite would orbit at an altitute of just 435 miles above the earth, compared with the 23,000-mile-high orbits of geostationary satellites. Each would include an Asynchronous Transfer Mode switch (controlled by a processor running Windows for Satellites, no doubt) because the primary aim of the system is to carry multimedia traffic to remote areas – meeting the demand of the US Clinton Administration that the Information Superhighway should be accessible to all. A problem with low earth orbit satellites however is that their lives are much shorter, and it is estimated that with 840 birds up there, one in 10 will tumble out of orbit every year, creating a requirement for an unprecedented satellite-building and launch programme. To minimise the launch costs and scheduling constraints, Teledesic’s satellites will be compatible with more than 20 launch systems around the world and will be self-stacking so that several satellites can be deployed by a single launch vehicle. Another problem is that Ka-band radio transmissions are absorbed and scattered by raindrops to a greater extent than conventional satellite transmissions. Teledesic is based at McCaw’s home in Kirkland, Washington, and AT&T Co is reported to be enthusiastic about the idea.
