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World War II Tech eLoran Deployed As GPS Backup In the UK

Posted by timothy on from the department-of-redundancy-department dept.

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.

16 of 139 comments (clear)

  1. Meanwhile, in the U.S. by Solandri · · Score: 4, Interesting

    Funny how two countries can take the exact same situation and arrive at completely opposite decisions.

    1. Re:Meanwhile, in the U.S. by FooAtWFU · · Score: 3, Interesting

      Well, the US operates the GPS system itself, which is a distinct advantage in a time of worldwide military conflict.

      --
      The World Wide Web is dying. Soon, we shall have only the Internet.
    2. Re:Meanwhile, in the U.S. by AchilleTalon · · Score: 3, Interesting

      Operating yourself the GPS satellites does not prevent disruption of the GPS service due to solar storms, which I believe is the most likely case behind the UK decision to keep the eLoran system. I don't neither believe shutting down selectively the service is possible in time of war. Remember the GPS communication is one-way only for the positionning devices. The satellite receives nothing from the device.

      --
      Achille Talon
      Hop!
  2. re Loran by freddieb · · Score: 3, Interesting

    I remember loran from my early ham radio days (50's and 60's). It made a hell of a noise on HF. It probably would not bother anyone any more as the hf frequencies are not utilized as they once were. Sounds like an excellent idea as the gps system is very vulnerable.

    1. Re:re Loran by clifwlkr · · Score: 3, Interesting

      Funny you say they are not being utilized. Last weekend the bands were jammed end to end for the world wide DX contest. On the major bands the waterfall was full end to end. I made hundreds of contacts. Earlier I did a summits on the air activation and made over 30 contacts in an hour. Never mind the digital modes. The ham bands are alive and well, Jim Olsen K7JEO

  3. Err - no. by queazocotal · · Score: 3, Insightful

    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.

    1. Re:Err - no. by Anonymous Coward · · Score: 5, Informative

      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."
      " .....

    2. Re:Err - no. by leathered · · Score: 4, Interesting

      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
  4. Pretty cool by Anonymous Coward · · Score: 5, Insightful

    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.

  5. Re:LMFAO by ColdWetDog · · Score: 3, Interesting

    in case of failure the consequences will be disastrous

    Yeah, because no shipping ever occurred before LORAN or GPS. What a joke! It's not like people found their way around the globe for centuries using the sun, moon and stars.

    Actually, we HAVEN'T been shipping super sized cargo ships without at least LORAN. The need for near continuous, weather independent localization pretty much coincided with the development of radio. We COULD develop different back up systems - for example inertial navigation systems have progressed from refrigerator sized boxes with a price tag suitable only for military ships to a shoebox sized box priced reasonably for a multi million dollar freighter. Subsequent improvement could probably decrease the size and cost but I doubt it would get to GPS sized dimensions - if only for the fact that the frequency requires longer antennas.

    And remember, a-Loran, b-Loran, c-Loran and e-Loran require multiple, expensive ground stations. We are all waiting to see what i-Loran will require, probably just some pixie dust and a persistent connection to i-cloud, but Apple hasn't weighed in with their plans just yet.

    --
    Faster! Faster! Faster would be better!
  6. "WWII tech" by CurryCamel · · Score: 4, Informative

    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

  7. Kinetic Kill Vehicle by haulbag · · Score: 3, Interesting

    Please understand that the technology to kill satelites has been around for a long time. Several military contractors for the US Defense Department have developed kinetic kill vehicles. They are in orbit as we speak. Their purpose is to destroy satelites by ramming into them at high velocity. They are like an anvil with a guidance system and a simple propulsion system. I know that Boeing had these back in the early 1990s. I'm sure there are hundreds or thousands of them up there by now with their targets locked in. If the US has them, you know the Russians and possibly the Chinese have them. If there is a major war between any of the major powers on Earth, the satelites will be one of the first casualties.

    Also, of course, the Chinese proved they could destroy satelites from the earth by their launch of a missile at one of their own several years ago. (Thanks for the space debris, China.)

    1. Re:Kinetic Kill Vehicle by haulbag · · Score: 3, Interesting

      With the GPS sats at a distance of 20k kilometers, you'd have plenty of warning to bomb the shit out of the attacking country before the kill vehicles could even approach the satellites.

      I never said that the first attack would be the satelites, but it very well may be. How much warning do you have when the KKV is already in orbit? All it has to do is change orbit slightly and your satelite is dead. Also, you suggest that a state would use nukes before their satelites are taken out. I don't agree. Whether you agree or not with the concept of MAD (mutually assured destruction), it is clear that the major nuclear powers do. It is quite conceivable that there could be a conventional conflict that would not escalate to a nuclear launch. In that case, taking out GPS would level the playing field for weaker nations and coalitions.

      http://en.wikipedia.org/wiki/Anti-satellite_weapon

      http://en.wikipedia.org/wiki/Militarisation_of_space

  8. HAM is not an acronym by xenoc_1 · · Score: 3, Funny

    How come slashdotters always write it as HAM? It's ham radio, not HAM. Despite rumors, it does not stand for Highly Antique Morse.

  9. US Navy still using sextant and chronometer by perpenso · · Score: 3, Interesting

    I saw a documentary on a US Navy Aircraft Carrier, it had a relevant incident. The carrier has GPS, LORAN, inertial navigation, etc. Yet every day a sailor steps outside the bridge with a sextant and takes readings on the horizon and sun. (does another sailor do so at night with the stars?). He then goes inside and using a WW2 manufactured mechanical chronometer calculates the position of the ship. When asked why the Navy still uses such ancient mechanical technology the sailor replied that this ship is a warship and is expected to be where it needs to be regardless of whether the fancy electronics is working or not.

  10. are you sure? by Phil+Karn · · Score: 3, Informative

    LORAN-C would probably be rather resistant to EMP. Like just about everything military, the transmitting equipment would be designed to be EMP-resistant, and receiving equipment on vehicles would not be particularly susceptible. It's stuff with long cables that picks up EMP. LORAN-C is certainly much more jam-resistant than GPS. The transmitter power levels are/were enormously higher, some in the megawatt range, to overcome natural background noise and antenna inefficiency. Even the large towers used are only a small fraction of a wavelength (3 km). Also, LORAN-C operates by groundwave propagation (that's why the frequency is so low) so it's not very sensitive to solar activity.