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The GPS Wars Have Begun (techcrunch.com)

Where are you? That's not just a metaphysical question, but increasingly a geopolitical challenge that is putting tech giants like Apple and Alphabet in a tough position. From a report: Countries around the world, including China, Japan, India and the United Kingdom plus the European Union are exploring, testing and deploying satellites to build out their own positioning capabilities. That's a massive change for the United States, which for decades has had a practical monopoly on determining the location of objects through its Global Positioning System (GPS), a military service of the Air Force built during the Cold War that has allowed commercial uses since mid-2000 (for a short history of GPS, check out this article, or for the comprehensive history, here's the book-length treatment).

Owning GPS has a number of advantages, but the first and most important is that global military and commercial users depend on this service of the U.S. government, putting location targeting ultimately at the mercy of the Pentagon. The development of the technology and the deployment of positioning satellites also provides a spillover advantage for the space industry. Today, the only global alternative to that system is Russia's GLONASS, which reached full global coverage a couple of years ago following an aggressive program by Russian president Vladimir Putin to rebuild it after it had degraded following the break-up of the Soviet Union. Now, a number of other countries want to reduce their dependency on the U.S. and get those economic benefits. Perhaps no where is that more obvious than with China, which has made building out a global alternative to GPS a top national priority. Its Beidou navigation system has been slowly building up since 2000, mostly focused on providing service in Asia.

17 of 210 comments (clear)

  1. All for one, and one for one. by Ostracus · · Score: 3, Interesting

    Kind of funny that the Chinese don't trust the Russians either otherwise they'd be using theirs.

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    1. Re:All for one, and one for one. by nojayuk · · Score: 5, Informative

      The US GPS, Chinese Beidou and Russian GLONASS are all positioning systems intended primarily for military use but which offer a degraded lower-accuracy signal for commercial and private users. The EU's Galileo navigation system offers precision to within a few cms, effectively military-grade accuracy, to paying commercial users as well as open but less-accurate position data similar to the "free" GPS, GLONASS and Beidou systems.

    2. Re:All for one, and one for one. by Entrope · · Score: 4, Interesting

      It's not really true any longer that the military signals provide better accuracy. DGPS approaches, including SBAS (FAA's WAAS being the first), can provide approximately the same accuracy as the military PPS, while also providing integrity assurances (in that domain's jargon, integrity means you have a bound on how wrong your calculated position is). The main advantage of the military signals now is improved availability, both in terms of anti-jamming and anti-spoofing measures.

      There is some advantage for military receivers in that they can use L2 to estimate dispersion due to the ionosphere, which is easily the largest source of errors for SPS receivers, but an increasing number of satellites transmit civil signals on a second frequency or use "codeless" approaches to make the same estimations using the military encrypted signals on L1 and L2.

    3. Re:All for one, and one for one. by nojayuk · · Score: 4, Informative

      Selective Availability was a deliberate degradation of the non-military positioning accuracy, "fuzzing" the reported position data. This has been switched off but the most accurate GPS signals are still encrypted and intended only for military and government use, even in the new more accurate GPS satellites being launched.

      The Galileo system provides that level of military-grade accuracy (to within a cm or so) to commercial customers, not just the military forces of participating countries and allied forces. It is still encrypted and requires payment and vetting of customers. Galileo's Open Service is accurate to 1 metre, a lot better than GPS' equivalent free service.

      It's entirely possible commercial pressures will mean higher-accuracy GPS signals might be made available to civilian users in the future but at the moment only Galileo can provide that sort of service over-the-counter.

    4. Re:All for one, and one for one. by Entrope · · Score: 3, Informative

      All else being equal, if you use N times as many satellites to compute a position/velocity/time solution, your expected accuracy improves by a factor of sqrt(N). But it's not quite that good when you have a multi-solution due to uncertainties in the system clocks between the constellations.

      Even in the ideal case, you can usually get more improvement from other techniques than just averaging more inputs. The first thing to attack is ionospheric delays, then a suite of several other errors that are similar in magnitude: GNSS ephemeris (position and velocity) errors, errors in the satellite clocks, other atmospheric delays, etc.

      Simple differential approaches use a receiver at a known location to compute (the sums of) several of those errors at each time of interest. Because a single receiver can't distinguish certain errors from each other, those corrections become less accurate over distance. More sophisticated approaches use a widely separated set of receivers to break the errors down into the individual components, so that the corrections can be applied over a wider area.

  2. Who cares? by nospam007 · · Score: 4, Insightful

    We just pay for our own satellites with our taxes and use all the other ones for free, just like everybody else.
    More satellites, more precision.
    I miss the 'war' part of the article.

    1. Re:Who cares? by digitig · · Score: 4, Informative

      I miss the 'war' part of the article.

      Back in the 1990s, the US DoD put out a statement that in the event of a conflict, GPS augmentation systems (which would now include things like the EU's EGNOS) would be considered a valid military target whether on friendly soil or not. It's part of the reason other States started to develop their own systems (except Russia, which was already well established with GLONAS by then).

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    2. Re:Who cares? by digitig · · Score: 5, Informative

      Thanks for crediting us here in the UK with Galileo, but it's an EU project, not a UK one, and we appear to be shut out of it because of Brexit.

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    3. Re:Who cares? by AmiMoJo · · Score: 5, Interesting

      There are a few of issues.

      When it was just GPS it was easier to jam/spoof. Now we can compare data from multiple systems to detect spoofing. Other services can provide greater precision than the US wishes civilians to have, or remove other restrictions like the maximum altitude and speed limits.

      It's a good thing.

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    4. Re:Who cares? by johannesg · · Score: 3, Informative

      Actually the UK is being shut out because _the UK_ demanded that non-EU nations would not have access, back when Galileo was being set up. In other words, it is the UK's own bloody fault for making that demand in the first place.

  3. Wrong story headline by LynnwoodRooster · · Score: 4, Funny

    Begun, the GPS wars have...

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  4. Re: Do GPS satellites have an off switch? by digitig · · Score: 4, Informative

    That is just *so* incorrect! The satellites send precise timing signals, along with two sets of orbital details: the almanack, rough positional information so the receiver knows which satellites to search for if it knows its approximate location and time, and the ephemeris, precise orbital information, for the actual position calculation. It works by measuring the time taken from the satellites to the receiver and triangulating from that (it actually does that in 4 dimensions, needing at least 4 satellites, because the receiver's clock won't be accurate enough to use the timing signals directly to work out the distance from the satellites). When it was introduced, the DoD only made one of the frequencies, L1, available and deliberately degraded it (which was called "selective availability"). That degradation was turned off in May 2000, and further enhancements to the civilian availability have been made such as the introduction of further signals that are easier to detect, make the satellites easier to locate, and compensate better for atmospheric effects.

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  5. Re: Do GPS satellites have an off switch? by mrclevesque · · Score: 4, Informative

    "Each GPS satellite continuously transmits a radio signal containing the current time and data about its position. Since the speed of radio waves is constant and independent of the satellite speed, the time delay between when the satellite transmits a signal and the receiver receives it is proportional to the distance from the satellite to the receiver. A GPS receiver monitors multiple satellites and solves equations to determine the precise position of the receiver and its deviation from true time. At a minimum, four satellites must be in view of the receiver for it to compute four unknown quantities (three position coordinates and clock deviation from satellite time)."

  6. Re: Payment by digitig · · Score: 3, Insightful

    The EU has, quite properly, been looking after the EU's interests. May still doesn't seem to have worked out yet what she wants. And Galileo isn't scheduled to provide full operational capability yet, so it's no big deal that it doesn't.

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  7. Re: Payment by Chris+Mattern · · Score: 5, Informative

    The UK is to the EU as the US is to NATO - pay for everything all the time

    Uh, what? Yes, the UK does net pay into the EU, as one would expect from one of its richer countries. Germany however, has a net contribution over twice that of the UK (larger as a share of its economy, too). France, too, gives more. This is largely due to the fact that the UK gets two-thirds of its net contribution back as a special rebate. In fact, if you look at net contribution as a share of the national economy, the UK comes in ninth.

  8. Re:Another fine example by Tyger-ZA · · Score: 4, Insightful

    Your entire response is a blind reaction to someone telling you that competition isn't always a good thing, built upon the strawman that redundancy does not feature in what I'm talking about, because I didn't explicitly write it down for you.

    This was an opportunity to think outside your box and you opted not to, so I'm going to break it down for you:

    The point I was trying to make is: "Competition can be counter productive for certain use cases", and this is one of those use cases.

    If your GPS goes down today, and for example you think everyone can just switch to a competing platform, go ahead and switch to BeiDou, Galileo or GLONASS right now and see how that goes. It may or may not work, depending on satellite coverage and/or the manufacturer of each device (most will likely be phones where they all support GPS but only a subset support a competing standard); therefore, your competing location services idea might not work for you as an individual, and certainly does not work for the entire group of people who depend upon GPS today. When shit happens, you'll find yourself using printed maps from a convenience store.

    Now for an alternative example that might work if the competitors could trust each other enough to collaborate, and if these collaborators could operate in a non malicious manner (the non malicious and trust aspects are the root problem):

    Instead of redundancy from many networks built around the premise that one could just switch to a totally alternative network, consider that at the hardware level a failure might look something like a satellite going down over one region, but there can be many replacements already in orbit ready to serve the exact same purpose for the same region, built by many different companies and/or governments, but built to work on the same communication protocols.

    Once that's in place the next step might be for the collaborators to design a "Next Gen" service together that may or may not be backwards compatible with their existing system. Some of the competitors might even want to start supporting some other frequency as a form of "let the market decide which technology is better" by having their new satellites support both the global standard and their own side show project.

    Consider how many satellite launches would be needed for such a system vs doing the same thing over and over for competing systems, along with all the other requirements for supporting it (such as ground stations for managing the satellites)

    Your internet is already a collaborative system that works (in the sense that you send bits on a wire without thinking "My bits can only go on the Verizon wires" ) yet you are arguing for the equivalent of this for your location services. The same applies for your road network (The Fords and the Teslas share the same road) and for your airlines (Different planes and airlines share the same airports)

    Your Fukushima example doesn't even make sense within the context of competing, or for preventing that specific failure in a reactor. Would multiple generators of the same bad design at Reactor A all failing at the same time, be solved by having Reactor B next door built by a competitor with a better design? No, Reactor A still fails and causes an environmental disaster. Your redundancy example only serves to provide backup sources of power if Reactor A goes down

  9. Re:My four year old supports herself by Anne+Thwacks · · Score: 3, Informative
    In fact the UK, since it joined the EU, has finally become independent in food production, thanks in no small part to EU farming subsidies. Which is quite a feat consider that was not the case like over a century.

    This is utterly incorrect. We import 3/4 of our food (the official figure is 66%) - which corresponds to 100% in the winder and 50% in the summer. Britain has not been self sufficient in food since the industrial revolution, and prior to then depended on large scale starvation to keep the population down. Our climate and geography make it impossible to grow food for much of the year.

    Most of the imported food (by volume) comes from the EU (on account of the Americas and Australia being a long way away).

    The main consequence of a no-deal Brexit will be no food in England. However, Boris and Rees-Mogg will be away in their holiday homes abroad, so they don't care. The impact on the rest of the EU will be fairly minimal except in a few industries. (Eg Farming in Spain will suffer a bit).

    Disclaimer: I spend 10 years working in food distribution in the UK.

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