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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.
The primary risk to GPS in the UK is the USA deciding to turn it off.
That risk doesn't apply for US shipping near the US, as if GPS was turned off - rather than severely degraded - so would the local LORAN locators.
GPS is not going away unless someone actually presses the button.
It's not vulnerable (theoretically) to single points of failure (ideally) as it's intended to carry on even in the event of moderate wars.
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.