Overview
The Iridium system ensures global coverage for communications based on a “constellation or grid” of 66 autonomously orbiting satellites, providing both mobile telephone and data services at a rate of 2400 bit/s.
Iridium is the low-earth orbit (LEO) wireless telecommunication network. These satellites – orbiting at a height of just 780 Km – are sufficiently close to the earth to pick up uplink signals from Iridium telephones and act as repeaters, in which the signals can move in space rather than through land-based cells. The ground stations, in fact, are interconnected via the satellite grid and not by means of land-based connections.