The consortium behind the Iridium global telephony system is to upgrade its network with an order for 81 new satellites worth $2.1bn (£1.43bn).
The contract was won by Thales Alenia Space to provide the new Iridium NEXT satellites which will replace the current network with 72 low-orbit devices, and an additional nine to be launched in the event of a failure or, as happened last year, an unexpected crash.
"Today marks a great milestone in Iridium's history. We operate the world's only communications system that truly works everywhere in the world, with more than 359,000 subscribers," said Matt Desch, chief executive of Iridium.
"By building a complete next-generation satellite system, and by securing export credit agency support of an amount sufficient to enable us to fully fund the project, we have completed critical steps in laying a strong foundation for Iridium's future."
The Iridium network was put into orbit in the late 1990s but soon ran into financial difficulties and went into bankruptcy owing to the limited market for a global mobile network.
The company was bought for a fraction of its original price and now runs as a private operation that contracts to a variety of business and military organisations.
Iridium is hoping that the new satellites will provide improved reception and data speeds, and allow new services to be developed that widen the company's limited user base.
"With our satellite design, Iridium will have a flexible platform for the delivery of existing and new services," said Reynald Seznec, chief executive of Thales Alenia Space.
"We will be supported by a broad consortium of world-class technical partners with extensive expertise in supporting critical missions of this scale and nature, and we expect 40 per cent of the work to be subcontracted to North American companies."
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