May 22, 1997. Copyright, 1997, Graphic News. All rights reserved
MOBILE GOES GLOBAL
By Danny Sullivan

LONDON, March 7, Graphic News- Plans for a truly mobile communication system that spans the globe have gone from the drawing board and into orbit. Iridium is a network of 66 satellites designed to let people speak to each other from anywhere on earth using portable phones. The first five Iridium satellites were launched on May 5, and launches will continue until mid-1998, until the entire network is in place.
Current communications satellites orbit high above the earth, up to 35,000km high. The powerful transmitters needed to reach these satellites make satellite mobile phones bulky, briefcase-sized contraptions. In contrast, the Iridium satellites orbit close to the earth, only 485 miles / 780 kilometers high. Transmitters need less power, allowing for hand-sized satellite phones similar to current mobile phones. In addition, calls can be made completely independent of ground-based switching networks. Most current satellite calls depend on ground-based switching at some point.
Testing of the satellites is currently underway. If all goes well, commercial service could begin in late 1998. Iridium backed by an international consortium of telecommunications and industrial companies, of which Motorola is the lead partner. The project will cost between $4 to $5 billion.
A competing network, Globalstar, also plans to be in operation that year. The first launches for that satellite system are scheduled for October. UK-based ICO plans a system to be operational in the year 2000.Teledesic, backed in part by Microsoft-mogul Bill Gates, also has a system on the drawing board, with launches planned for 2001. 

Sources: Iridium, Globalstar, Analysys Limited