Why did Iridium choose low-earth orbit (LEO) satellites?
Iridium chose LEO satellites because this configuration offers a number of benefits to customers. Unlike geosynchronous satellites, which hover about the equator at an altitude of 35,900 kilometers (22,300 miles), the Iridium constellation of 66 satellites are in polar orbits at an altitude of only 780 kilometers (485 miles). This orbital configuration provides the following benefits over systems based on other orbital configurations: No significant transmission delays; small, handheld pagers and phones (versus laptop-size terminals); lower transmit power resulting in longer battery life; and complete global coverage, including all oceans and all land areas including the Poles.
