Data Network Services



The Iridium satellite network includes three principal components which include the satellite network, the ground stations and the satellite phones and data units.
Voice and data messages can be routed anywhere in the world by the Iridium network. Calls are relayed from the satellite phone or data unit on the ground to one of the Iridium satellites. It is then relayed from one satellite to another then down to an appropriate ground station. The call is then transferred to the public voice network or Internet when it reaches the recipient.

The Iridium constellation includes 66 satellites flying in six orbital planes with 11 satellites equally spaced apart from each other in that orbital plane. The satellites have polar orbits at an altitude of 485 miles.

The satellites communicate with each other using Ka-band inter satellite links. Each satellite has four inter satellite links, two to the fore and aft satellites in the same orbital plane and two to the satellites in orbital plane to either side. These inter satellite links allow calls to be routed among the Iridium satellites before being transferred to a ground station. This inters satellite links makes Iridium impervious to natural disasters like hurricanes or earthquakes which can damage a ground station. If a ground station is damaged the Iridium satellites can rout the call to another ground station.

Each satellite completely orbits the earth in 100 minutes traveling at 16,832 miles per hour. From horizon to horizon it takes 10 minutes. As satellites move out of view from the satellite phone user the call is handed over to the next satellite coming into view.

The Iridium ecosystem of over 200 partner companies continues to establish Iridium products and solutions as industry standard across Maritime, Aviation, Government, Land/Mobile and M2M markets worldwide. With Iridium at the core of this highly robust network, the ecosystem presents customers around the world with a promise of truly global and reliable coverage, unmatched by any competitor.

Global Star


Globalstar’s constellation is made up of 40 (LEO) satellites with an additional four satellites in orbit as spares. The satellite design is very simple. Each satellite consists of an antenna, two solar arrays, a magnetometer, and a trapezoidal body. The Globalstar constellation orbits at an altitude of approximately 1,500 kilometers of (876 miles). First generation Globalstar satellite weighed 550 kg. Their second generation satellites will weigh substantially more. Globalstar satellites orbit with an inclination of 52 degrees. Because of this and the fact the satellites lack inter satellite linking the constellation picks up signals from over 80% of the planet excluding the extreme polar regions and some ocean regions.

The satellites are simple repeaters or mirrors in the sky. Globalstar calls this “bent pipe” technology. Voice and data transmissions come up from the satellite phone or data device to one of the 40 satellites, that signal is then bounced back down to one of the ground gateways where it is transferred to the public switched telephone network and/or the Internet. Global Star have more than 315,000 subscribers (as of June 2008), Globalstar is the world’s largest provider of mobile satellite voice and data services.[citation needed] Globalstar offers these services to commercial and recreational users in more than 120 countries around the world.

Products include mobile and fixed satellite telephones, simplex and duplex satellite data modems and satellite airtime packages.
Many land based and maritime industries make use of the various Globalstar products and services from remote areas beyond the reach of cellular and landline telephone service.

Global customer segments include: oil and gas, government, mining, forestry, commercial fishing, utilities, military, transportation, heavy construction, emergency preparedness, and business continuity as well as individual recreational users.