Emma Kelly/LONDON
Inmarsat expects to announce by August contractors and vehicles to develop and launch its fourth generation of satellites after board approval for development of the new $1.4 billion system and the release of request for proposals (RFP) at the end of last year.
The process is on track, with RFP responses for the Inmarsat-4s received and the negotiation and evaluation period under way, says Inmarsat.
The main focus is on satellite development, for which Inmarsat has received three bids, it says. The space segment will comprise two satellites, located at 64°E and 54°W, with a third satellite as a ground spare in case of a launch failure (Flight International, 8-14 December, 1999).
Inmarsat's current satellites - the Inmarsat-3s - were developed by prime contractor Lockheed Martin and payload provider Matra Marconi Space. The five satellites were launched by Lockheed Martin Atlas, Russian Proton and Arianespace Ariane 4 vehicles. The 5t Inmarsat-4s will require launch by vehicles such as the Ariane 5, Proton Breeze-M or Sea Launch.
The Inmarsat-4s, which are due in service by the end of 2004, will be designed for multimedia personal communication services, offering data rates up to 432Kbit/sec. These high rates will be possible through the use of spot beam technology, which was first used on the Inmarsat-3s. The new satellites will feature 200 narrow spot beams and 19 wide spot beams, with the beams focused on major land masses to meet the requirements of land users - the largest market for Inmarsat services.
Inmarsat land users are likely to benefit most from the Inmarsat-4s, but aeronautical users will accrue "even lower costs and further service enhancements", says David Featherstone, head of Inmarsat's aeronautical operations. Commercial airline and corporate aircraft users of the Inmarsat system - 3,500 aircraft - will benefit from higher data rates at a lower cost per bit, allowing "cost effective information transfer by satellite" and a broader range of communication and entertainment applications, says Featherstone.
The data rate for aeronautical users will increase this year with the launch of Inmarsat's high-speed data rate of 64Kbit/sec, up from 10.5Kbit/sec. System design of the 64Kbit/sec service has been completed and ground and airborne equipment is under development, he says.
Source: Flight International
