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World War II Tech eLoran Deployed As GPS Backup In the UK
hypnosec (2231454) writes General Lighthouse Authorities (GLA) has announced that they have deployed a World War II technology called Long Range Navigation system, which they have named eLoran, in seven ports across Britain to serve as a backup for the existing Global Positioning System (GPS). GLA notes that modern ships have a lot of equipment that rely on Global Navigation Satellite Systems for functioning and in case of failure the consequences will be disastrous. For this reason technology that doesn't rely on the GPS was required as a backup. eLoran is a ground-based system rather than satellite-based and is designed to be used in the event of a GPS failure. The system was quite successful and post-WWII era, the system was updated and crowned a new name Loran-C. The navigation system was adopted by mariners across the globe and was used until GPS was deployed. Loran has now been renamed as eLoran because of the upgrades to the technology as well as the infrastructure. The more accurate system generates longwave radio signal, which is 1 million times more powerful than those from positioning satellites, are capable of reaching inside buildings, underground and underwater. According to GLA, eLoran and GPS are quite different from one another and hence there is no common mode of failure.
Funny how two countries can take the exact same situation and arrive at completely opposite decisions.
This is not your old 70's LORAN system. Thanks to advances in DSP processing, eLORAN gives your position with precision comparable to GPS (10m or so). It also have data channel that's used to broadcast DGPS corrections, so it complements GPS nicely.
Because of low frequency, signal penetrates buildings and ground (however with greatly reduced range). This may be one of the solutions for a car navigation in tunels. Even if it produces less precise position, it's always better than no position at all.
Great contrast between UK and USA, where LORAN transmitters were demolished in the past years. When so many things dependd on GPS signals, we really need some backup system for precise timing and positioning. Not thinking about backup only means we will learn about it the hard way - and it will not be pretty.
sorry but you are wrong - .....
From
http://www.bbc.co.uk/news/science-environment-29758872
"
The system works using a fleet of satellites orbiting high above the Earth, but the signal they transmit is weak and can be easily interfered with.
Other sat-nav systems - such as Galileo in Europe and Glonass in Russia - have the same vulnerabilities, says Prof David Last from the Royal Institute of Navigation.
"A little bit of power from a jammer on the frequency used by GPS close to your receiver can deafen it, and it won't be able to hear the GPS signals," he says.
"For example, jamming is a real issue in Korea. There have now been three occasions when the North Koreans have transmitted high-powered jamming in South Korea."
The Sun too can knock satellite systems offline, he adds.
"It starts to transmit radio noise during solar storms, so intense that it either makes GPS positions wobble about or causes GPS to be lost across the entire sunlit side of the Earth."
"
In case anyone is intersted, this slideset gives a nice overview of this "WWII tech".
http://www.ursanav.com/sites/default/files/pdfs/news/UrsaNav%20ILA-40%20eLoran%20System%20Definition%20%26%20Signal%20Specification%20Tutorial.pdf
In the UK pilots often receive NOTAMs stating that the military are conducting GPS jamming trials in certain areas. From personal experience and reports from other pilots the jamming is very effective.
For all intensive porpoises your a bunch of rediculous loosers