Inmarsat launches I-4 satellite:
RBGAN expanded coverage by June

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On March 11, the world’s largest communications satellite was launched into a stationary orbit 22,000 miles above the Indian Ocean. Known as the “I-4,” the 6-ton satellite is owned by Inmarsat, Ltd., and is expected to be operational by 4th quarter, 2005. Its launch signals the convergence of four trends that are making remote voice and email communications more affordable than ever in Asia, Africa, and other regions.

Three of these trends have been increasingly evident over the last five years: the popularity of small, portable “satphones” and satellite data modems; the growing use of these devices for email; and expanding territorial coverage.

To these may now be added a fourth: steady and significant reductions in the price of service and hardware, creating new opportunities for communities, humanitarian development projects, and field teams in remote areas.

The new I-4 satellite will expand the coverage area of the RBGAN1, a lightweight (3.3 lb) data modem that has performed with distinction since its introduction in 2003, currently covering the Middle East, Western and Central Africa, and Central Asia. The I-4 satellite will extend this coverage to Southeast Asia, the Philippines, Indonesia, and most of Australia2.

Pennies per message. What does it cost to send and receive email over RBGAN? Fortunately, the trend toward lower prices is on a path toward the proverbial “penny email.” A small text message of 4 kilobytes will cost about 3 cents3. A larger email of 20 kilobytes would cost around 15 cents; a 100-kilobyte attachment, about 70 cents.

Usage prices have dropped by over 50% since the RBGAN’s introduction less than two years ago, and rates continue to decline. The cost of a new modem, once $2000+, is now under $900.

More bandwidth, more choice. When the first two I-4 satellites complete testing and are commissioned, the service will drop the “R” and become simply BGAN. Current R-BGAN modems are compatible with the new service. However, the I-4 will enable Inmarsat to offer a much greater bandwidth: a maximum of 432 kbps, triple the current capability.

Even though the RBGAN will work over the new Inmarsat I-4 satellite, its speed will not increase above its original 144 kbps. To take advantage of the near-broadband speed of 432 kbps, users will have to purchase a new BGAN terminal. Currently, four manufacturers are planning to offer BGAN terminals, which vary in size, weight, pricing and features. Not all of the terminals being produced will be capable of 432 kbps, but there will be more options for specific customer requirements.

RBGAN and the next-generation BGAN have other features and options, including external antenna kits which will allow the user to work from an indoor office. The most important precaution for first-time users, however, is to research the different service providers carefully. While there are many airtime pricing packages available, the primary cost control factor is the management of unwanted data transfer over the satellite. The best services understand this and have provisions for limiting and monitoring excess usage.

Value bandwidth – within reach. High bandwidth at affordable prices has been a long-sought prize in the aid and development community for many years, and it is now within reach. As the four trends continue in favorable directions, full Web access – not limited to email - from remote locations will also become a more affordable possibility, perhaps in two or three years. Well-designed “lean” Web sites will help as well.

Customers of communications services will continue to have many choices, if they are informed of the opportunities available. Web technologies, enabled by portable satellite field communications, now make it easier than ever to keep humanitarian teams and managers informed – wherever they work. They, and the people they help, all will benefit.


  1. Regional Broadband Global Area Network.
  2. A second satellite is planned to be launched in 3rd quarter 2005 and will cover the Western Hemisphere. A third has been built as a spare but may possibly be used to cover the South Pacific.
  3. Excludes any activation and/or monthly fees that may apply to the R-BGAN service. These fees vary per airtime service supplier.