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Location: Patterson, New York | Subject: New Communication Technology for Subs
Raytheon to deliver 'paging system' for submarines
By Lewis Page
Published Thursday 15th November 2007 16:27 GMT
US arms behemoth Raytheon has won a $5.2m contract to deliver its Deep Siren "tactical paging system" for submarines to the US navy.
Submarines, being underwater, are often hard to get in touch with. The only kind of radio which works at all is very-long-wavelength, which can be used to contact subs trailing special antennae provided they aren't too deep. This solution has sharply limited bandwidth and only works shore-to-ship. The only other option, historically, has been for the sub to come to persicope depth and put up a comms mast.
All this has meant that submarine captains were only in touch with higher authority at predetermined times, when they would slow down, come shallow and stream longwave receiving antennae - or put up masts - according to previous orders. If the sub was running fast and/or deep, tough. There was often no way to contact it. The submarine skipper remains one of the last of the truly independent decision-makers, living a blissful life out of touch with his bosses sometimes for weeks on end.
That was OK for the Cold War, when most of the subs' business involved independent, strictly maritime missions. Nowadays, however, the underwater warships need to get involved in modern combined operations, for which their new bosses would like to be able to reach them more easily - just like the hapless modern wage slave with his BlackBerry.
Hence Deep Siren, which is a fairly basic idea. A surface or air boss wishing to get in touch with a sub drops a small disposable buoy into the sea somewhere within a few tens of miles of the sub's location. The buoy has Iridium satcomms, allowing it to connect to the US military's Global Information Grid comms infrastructure.
From the buoy, the signal is passed on via an acoustic signal which can be picked up by the sub up to 50 miles away. The system is one-way, hence "paging system". The acoustic signal is unavoidably low-bandwidth, but then so is Iridium.
Each buoy can last for three days, including up to 30 minutes of acoustic transmissions, according to the Raytheon data sheet (http://www.raytheon.com/products/stellent/groups/public/documents/content/cms04_023434.pdf).
Raytheon got the job of developing Deep Siren back in 2005, and this latest contract is for delivery.
"Submarine communication protocols are much the same as they were 60 years ago," said Raytheon's Jerry Powlen.
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New Communication Technology for Subs
