There are several global and regional satellite operators. Below I’ve listed a brief overview of the existing and potential operators. I looked up this information when researching RTLS (Real-time Location Solutions). It is pretty basic, but hopefully you’ll find it useful.

• Iridium
  • 66 operational LEO satellites + 14 in-orbit spares
• Globalstar
  • 48 LEO satellites that relay messages to ground-based gateways (then call passed to Internet and terrestrial telephone network)
  • Can maintain connection using the same IP address
  • Coverage
    • Covers the US from 70 degrees north to 70 degrees south
    • Covers 80% of the world’s landmass (excluding Antarctica) and territorial waters in North America, South America, Europe, Asia, Australia, and New Zealand
  • Offers “secure asset tracking” service (small modem placed inside shipping container serving as tracking system, modem programmed to track container’s position)
  • Has three times more overall capacity than Iridium (in 2003 Globalstar’s capacity was seven million users or devices)
  • The maximum voice and data capability is 9.6 kilobits (four times faster than Iridium)
    • Globalstar also has multi-channel modems offering up to 144 kilobits data transfer
• Orbcomm
  • Has 30 low-earth orbit (LEO) satellites
  • Trades on the Nasdaq under ORBC
• Inmarsat
  • Has over 24 Earth Stations and 4 active geo-synchronous orbits (GEO) satellites, providing Global satellite coverage
  • 62 member-country, internationally owned cooperative, formed over 20 years ago
  • Communications at up to 64kbit/s to over 210,000 ship, vehicle, aircraft, and portable terminals
  • New Inmarsat I-4 satellite system, which since 2004 supports Inmarsat Broadband Global Area Network (B-GAN) offering mobile data communications up to 432kbit/s
• Thuraya Satellite Communications Company
  • Provides blanket coverage to 99 countries spanning Europe, North and Central Africa, Middle East, Central Asia, and Indian Subcontinent (approximately 40% of the world’s population)
• Mobile Satellite Ventures (MSV)
  • Has 2 MSAT (Mobile Satellites)
  • Covers most of North America, Central America, and the Caribbean
  • launched in 1995 and 1996, plans to launch replacement satellites in 2009
  • parent company SkyTerra trades on OTC as OTC:SKYT
• ICO Global Communications
  • Attempting to build a “next generation” network through satellites and terrestrial stations
  • Merged with Teledesic

Types of Satellite Networks

LEO (Low Earth Orbit)

Small non-geostationary satellites 485 miles high, operate in LEO, providing mainly mobile data services (e.g. Orbcomm)

Big LEO (Low Earth Orbit)

Larger non-geostationary satellite operates in LEO, providing mainly mobile telephony services. Many of new proposed ‘global mobile phone’ services are provided by this type of satellite. The satellites are located between 700km and 1,500km from Earth (e.g. Iridium, Globalstar)

MEO (Medium Earth Orbit)

Non-geostationary satellites providing mobile telephony services located 10,000km from Earth (e.g. ICO)

GEO (Geostationary)

Satellites occupying an orbital position 36,000 km above the earth that remain in a stationary position relative to Earth (e.g. Thuyara, Inmarsat)