How a LEO System Works

Three fourths of all new satellites launched in the next decade will fly close to the Earth's surface, in low-Earth orbit, between 400 and 1,000 miles up. The new satellites will carry calls from hand-held phones and, depending on the system, low and high-speed digital data. Customers include international travelers, far-flung corporate offices, and people in remote areas of the developing world who today have no access to phones.

Digital Mobile Phones: Includes hand-held units that can talk both to satellites and to local cellular phone systems and fixed units in cars, planes, and ships.

Home PCs: For systems such as Teledesic that propose to offer broadband satellite connections as good as fiber-optic cable, individuals could tune into the Internet from home with a dish antenna similar to those used by Direc TV.

Solar-Powered Phone Booth: Could be located anywhere, such as in a Third World village square where phone service does not exist today and it would be too costly to run wires.

Data Communicator: Inexpensive low-power devices send and receive short data messages, including to and from Internet addresses. When combined with GPS receiver, they transmit their location, an aid to search and rescue operations anywhere. They can be mounted on trucks and barges so companies know where their assets are located.