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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.
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.
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.
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).
Quidnam Latine loqui modo coepi?
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.
Quidnam Latine loqui modo coepi?
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.
Quidnam Latine loqui modo coepi?
"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)."
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.
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.