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China's GPS 'rival' Beidou
- sbradford26 8y agoGPS has become so ubiquitous I honestly forgot that it was something that could be owned. It is cool to see some competition in the GPS world.
- nutjob2 8y agoGPS systems are not so much 'owned' as 'paid for'.
- azinman2 8y agoAnd designed and maintained...
- tinus_hn 8y agoGPS is aging technology, its satellites are dying already and its limits are showing clearly. It won’t be around forever.
- dleclere 8y agoThat's not true... The U.S. is actually in the process of launching the next generation of GPS satellites.
- Analemma_ 8y agoIt’s interesting and odd to me that Beidou requires two-way communication, as opposed to other satellite tracking systems where the receivers are purely passive and satellites only transmit, not receive. Is there an explanation for why this was done?
- craftyguy 8y agoUnavoidable collection of user location data is the obvious reason. I would absolutely stay away from any device that has support for this positioning technology.
- wbraun 8y agoThe article talks about how it can be used to send messages but my first thought is that it could allow tracking of receivers. A scary thought if it does achieve widespread adoption.
- majia 8y agoThere are two different and independent beidou systems. One is passive and cannot track receivers, and the other is similar to a simple satellite internet.
- _Gyan_ 8y agoAppears that two-way comms was required for Beidou-1, not BeiDou-2. See https://space.stackexchange.com/questions/30839/is-two-way-communication-really-required-to-use-beidou-gnss https://space.stackexchange.com/questions/30839/is-two-way-c...
- nraynaud 8y agoI am highly skeptical of this claim, it's either for higher accuracy of military stuff, or an internet connexion to get a key or the ephemerides or something. But nobody is sending signal to a satellite 21000km from the surface straight from a watch-sized device.
- tialaramex 8y agoI agree with the thrust of your post, but Um Actually... The current Breitling Emergency (a bulky men's watch, but it wouldn't look out of place on some big out-of-doors type guy's wrist) is a working PLB transmitter. So that means signals from it can be received not just 21000km up, but 36000km up where Geostationary birds live. If you activate it, that watch will transmit the digital signal with its unique ID in it, and assuming you filled all the paperwork out soon after somebody from the relevant local emergency response (maybe a coastguard, mountain rescue, that sort of thing) will be phoning your emergency contacts "Hi, do you know nraynaud? They went flying today? OK, do you know where they were headed? We have an emergency transmission from their beacon so we're going to send somebody to take a look and check they're OK. We'll let you know, thanks". A "real" beacon would be better, more robust, better battery life, easier and more obvious for random strangers to operate if you're unconscious, not to mention much cheaper. But the Emergency has the advantage that you'll actually have it when shit goes wrong, because it's your watch.
- deleted 8y ago[deleted]
- tialaramex 8y agoI suspect this is either a misunderstanding or just copy-pasted from descriptions of a different earlier system. It doesn't make any sense to have the ground station transmit to figure out its location. To give a baseline, that's how the original analogue COSPAS SARSAT worked last century, using doppler measurements to get a location over time - and its accuracy was appalling, a human operator has to use equipment to narrow down where the signal is, it takes significant time to get a 1 nautical mile search area. Which is much better than "I dunno, in the sea?" for a lost ship or plane, but you're still going to need a serious search-and-rescue operation to find anybody. A modern digital COSPAS SARSAT system you may have seen if you're a serious hiker or outback flyer just does GPS, it uses GPS to figure out where it is, then sends a digital signal that says "I need help, here are my GPS co-ordinates" hence the slogan "Taking the search out of search and rescue".
- baybal2 8y agoYes, first generation beidou were mandatory two way, to do crypto handshake. The Party wanted "more control," just as usual. The idea was realisedly lunatical even back then, but party boffins really though that reality and laws of physics will yield to party's mandate.
- majia 8y agoIt’s not about “more control”. The first beidou was two way mainly because they need some kind of satellite phone functionality.
- baybal2 8y agoThat what was said to the populace. In reality, first gen beidou sats already had functionality to provide atomic clock signal and advanced station keeping. The accuracy was quite lower than from leo GPS sats, but still. The explanation that beidou 1 was a glorified, super expensive satellite pager, with navigation functionality as an afterthought does not hold water. This "explanation" came much later than the commencement of beidou 1 project.
- majia 8y agoLooks like some misunderstanding here. No one ever claimed Beidou I was developed as a satellite pager. The reason Beidou I needs two way transmission is they wanted add pager functionality to its navigation functionality. The party wants more control has nothing to do with Beidou I's two way transmission mechanism. When Beidou I was developed, it's mostly used by military. The party doesn't need "more control" there.
- baybal2 8y agoMilitary use??? You understand what two way transmission means during a conflict? An enemy tunes an antiradiation missile on your frequency, and voila... China already had military digital satellite coms working by late nineties. For them, it was of even lesser utility.
- justfor1comment 8y agoIndia did something similar a few months ago. Each country wants to build it's own GPS for military purposes. At some point we have to stop calling it 'Global' Positioning System.
- nradov 8y agoThe generic term is Global Navigation Satellite System (GNSS). GPS is one type of GNSS.
- kec 8y agoThe "global" refers to the fact that it works globally, not that it exists for the good of humanity. Navstar (owned by USDoD, what is commonly called "GPS"), GLONASS and soon Galileo all have global coverage.
- romwell 8y agoYup, GLONASS = GLObal NAvigational Satellite System. Although one should note that name is the intention; it has not always had global coverage (it does now), and may not always have global coverage in the future (say, if they decide to increase the precision in a strategic area at the cost of loss of coverage in others).
- thaumasiotes 8y agoI really don't see a problem with describing any and all systems that tell you your position on the globe as "global positioning systems".
- tinus_hn 8y agoJapan has its own positioning satellites (QZSS) that are only visible from the region around Japan. It’s designed so positioning works if you’re in a city with skyscrapers.
- everybodyknows 8y ago>... even precision missiles. So if GPS were to be jammed, or disabled by a hack into the ground control systems -- PLA missiles would still work just fine. Hmm.
- ElBarto 8y agoIt would be unwise for Chinese missiles to use a positioning system controlled by the US military, to say the least...
- craftyguy 8y agoDue to COCOM limits, GPS was never an option for China to use on their missiles. https://en.wikipedia.org/wiki/CoCom#Legacy https://en.wikipedia.org/wiki/CoCom#Legacy Edit: I'm wrong.
- Retric 8y agoCOCOM is a non issue when building your own devices from scratch. GPS satellites are transmit only so they can’t impose such limits directly it’s device manufacturers that implement COCOM.
- snops 8y agoYou are right that COCOM is not the issue, but there are other measures. The new military M code transmitted from the latest satellites is encrypted with a frequently changing key, so in the event of a war the DOD can disable the civilian signal as the M code will work standalone, hence a third party nation cannot rely on GPS. The previous P(Y) code was also encrypted, but is theorised to need the civilian C/A code as well to work.
- eiaoa 8y ago> so in the event of a war the DOD can disable the civilian signal as the M code will work standalone, hence a third party nation cannot rely on GPS. They also had the option in older satellites of turning on selective availability, which would degrade the civilian location service from 5-meter to 100-meter accuracy without affecting the military service. Purportedly newer GPS satellites don't have the option anymore. https://en.wikipedia.org/wiki/Error_analysis_for_the_Global_Positioning_System#Selective_availability https://en.wikipedia.org/wiki/Error_analysis_for_the_Global_...
- csense 8y agoSo China has the technology to destroy satellites [1], and is developing alternatives to US satellites. Does this make anyone else nervous? Maybe Trump has a point when he says we should stop letting China steal our technology. [1] https://en.wikipedia.org/wiki/2007_Chinese_anti-satellite_missile_test https://en.wikipedia.org/wiki/2007_Chinese_anti-satellite_mi...
- weregiraffe 8y ago>So China has the technology to destroy satellites [ Any country that can launch a satellite has a technology to destroy one. It's called a missile. You don't even need to go to orbit - just intersect the orbit of the target and dump a bucket of nails in its path.
- age008 8y agoAren't GPS satellites geostationary?
- detaro 8y agono, they are not.
- JumpCrisscross 8y ago> Any country that can launch a satellite has a technology to destroy one It's easier to put something in orbit than to knock something out of orbit.
- slededit 8y agoYou can destroy something without taking it out of orbit. The pieces will happily carry on along their orbital trajectories.
- JumpCrisscross 8y agoIt's easier to put something in orbit than to hit something in orbit.
- majia 8y ago"We are likely to see an increased bifurcation of the world into two camps - 'pro-China' and 'pro-US'", says Blaine Curcio, founder of Orbital Gateway Consulting Why do some people view it as a with-us-or-against-us problem? Combining beidou with GPS gives a better accuracy. Some competition and collaboration in the GPS field can benefit us as a whole.
- rrggrr 8y agoI wouldn't want to be navigating critical transportation during a dispute between China and the United States with this track record (would you?): http://fortune.com/2018/08/28/china-has-been-withholding-bird-flu-samples-for-a-year-heres-why-thousands-could-die/ http://fortune.com/2018/08/28/china-has-been-withholding-bir... https://www.wired.com/story/australias-ban-on-huawei-is-just-more-bad-news-for-china/ https://www.wired.com/story/australias-ban-on-huawei-is-just... https://nypost.com/2018/09/19/chinas-social-credit-system-is-a-real-life-black-mirror-nightmare/ https://nypost.com/2018/09/19/chinas-social-credit-system-is... http://fortune.com/2016/05/20/chinese-social-manipulation/ http://fortune.com/2016/05/20/chinese-social-manipulation/
- z2 8y agoIt's precisely the fear of having navigation turned off that led to nations launching their own GPS alternatives. More satellites is better for critical transportation if one nation (be it China or US) wants to turn disable their system for civilians.
- nradov 8y agoEventually most mobile devices will contain a single chip that supports GPS, GLONASS, Galileo, Beidou, and other smaller regional GNSS's. They all rely on somewhat similar technology so it's mainly a software problem.
- liftbigweights 8y ago> "We are likely to see an increased bifurcation of the world into two camps - 'pro-China' and 'pro-US'", says Blaine Curcio, founder of Orbital Gateway Consulting Why just two? If our stranglehold on the world breaks, the EU and Russia are easily capable of carving out their sphere of influence. People really underestimate how populous and wealthy and powerful the EU is. It's strange how the narrative changes in such a short time period. Just 10 years ago, I remember people talking of "chimerica" as if the US and china were going to merge into a single world ruling entity.
- kejaed 8y agoNote you can buy off-the-shelf GPS modules today that will work across all four GNSS: https://www.u-blox.com/en/product/neo-m8-series https://www.u-blox.com/en/product/neo-m8-series
- donquichotte 8y agoExactly. At the moment, the consumers benefit from the increased accuracy and coverage provided by multiple GNSS. Sidenote: the ublox M8 chips are a pleasure to work with, and there are variants that have IMUs (gyros and accelerometers) on board for sensor fusion. All for <10$. What an exciting time we live in!
- eiaoa 8y ago> Sidenote: the ublox M8 chips are a pleasure to work with, and there are variants that have IMUs (gyros and accelerometers) on board for sensor fusion. All for <10$. What an exciting time we live in! I wish someone would build a USB data logger using one of these. I still use one to geotag photos and record trips, but all the available models use old GPS-only chips and can be pretty jumpy when reception is poor. Having one that fused multiple GNSS and had an IMU to smooth out some of the random jumpiness would be ideal.
- cronix 8y agoYep, we use those in (hobby) drones for extra precise location data.
- walrus01 8y agoOne of the reasons for this, about seven years ago Russia put a 30%+ import tariff on any mobile phone that didn't work with GLONASS. Thereby motivating chipset makers like Qualcomm to integrate GLONASS receive features into their existing RF chipsets.
- nabla9 8y agoMulti-GNSS support increases the reliability and signal availability. Commercial chipset will usually add support for all of them and don't just choose one. Newest phones (like iPhone 8) work with GPS, Galileo, Glonass, and QZSS. Beidou support will come in the future.
- comboy 8y agoWhy is 'rival' quoted?
- nutjob2 8y agoBecause GPS do not rival each other in any practical sense, instead they complement each other. More GPS systems means more satellites means greater accuracy for users. Let's hope even more countries get into GPS "rivalry."
- comboy 8y agoOh, I guess you're right. In my mind it was like "not really a competition" in a negative aspect but it turns out the negativity was in my mind.
- deleted 8y ago[deleted]
- tyingq 8y agoI was curious what Beidou meant, apparently it refers to the "Big Dipper": https://en.wikipedia.org/wiki/BeiDou_Navigation_Satellite_System#Nomenclature https://en.wikipedia.org/wiki/BeiDou_Navigation_Satellite_Sy...
- jewelry_wolf 8y agoYep, Big Dipper as part of Ursa Major translates to something used as a wine vessel about 2 to 3 thousands year ago. https://en.wiktionary.org/wiki/%E6%96%97 https://en.wiktionary.org/wiki/%E6%96%97
- pietroglyph 8y agoNo one seems to have mentioned that the US has actually blocked GPS signals before for military reasons (during the Kargil war in 1999): https://timesofindia.indiatimes.com/home/science/How-Kargil-spurred-India-to-design-own-GPS/articleshow/33254691.cms https://timesofindia.indiatimes.com/home/science/How-Kargil-... There's a good reason and precedent for China (and others; see GLONASS, IRNSS, Galileo) to be afraid of this.
- jhayward 8y agoNo, the US has never done any blocking in the GPS system. The article refers to a request by India for access to the military GPS signal and military equipment, which was not granted. The US, as well as virtually all other technological powers, does have the capability to jam GPS signals using ground, sea, or air-based jamming platforms but those are not part of the GPS system.
- qume 8y agoYup it did - I was flying aerial surveying at the time. Bad timing. Actually I didn't notice anything in the end so was all good but when I saw the NOTAM I couldn't believe my bad luck. Edit - link: https://www.theregister.co.uk/2016/06/07/us_military_testing_gps_jamming/ https://www.theregister.co.uk/2016/06/07/us_military_testing...
- jhayward 8y agoNot sure whether you're agreeing or disagreeing, but that refers to jamming done by electronic warfare units, not part of the GPS system, as I indicated above.
- pietroglyph 8y agoThe United States actually does have the ability to selectively degrade signals. I don't know enough to comment on this capability in more detail (another comment seems to indicate that it is through jamming). A relevant excerpt (from 2000) is below: > Additionally, we have demonstrated the capability to selectively deny GPS signals on a regional basis when our national security is threatened. https://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/techops/navservices/gnss/gps/policy/presidential/index.cfm?print=go#1 https://www.faa.gov/about/office_org/headquarters_offices/at...