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Last satellite in the Indian Regional Navigation Satellite System launched
- nautical 8y agoReason to start working on the system as per the article : "It is a culmination of 17 years of rigorous work by Indian space scientists. India took a firm decision on IRNSS in 1999 after the US government refused to share GPS data that would provide vital information on Pakistani troops position during Kargil war. As in the previous launches of the IRNSS satellites, PSLV-C41 has also used ‘XL’ version of PSLV equipped with six strap-ons, each carrying 12 tonnes of propellant."
- andyjohnson0 8y agoI didn't understand this. How would the GPS system allow the US to know the location of Pakistani soldiers? GPS satellites only transmit and GPS receivers only receive - there is no return path that would disclose the location. What am I missing?
- nacnud 8y agoOnly a guess, but at that time wasn't the GPS signal intentionally degraded for non-US-military use, with reduced accuracy? Perhaps they're talking about the more precise signal, which the US didn't let them use.
- andyjohnson0 8y agoYes, "selective availability" was still in use then - but I can't see how its use or not would disclose a GPS user's position.
- Arnt 8y ago"I need a missile strike. My position according to GPS is x and the Pakistani you should hit are 920m straight north of me according to my rangefinder."
- rajeshpant 8y agoIts not about location of foot soldiers. Although the article highlights about GPS, it is mapping in general. India wanted terrain and altitude data for making strategy.
- hshehehjdjdjd 8y agohttps://m.timesofindia.com/home/science/How-Kargil-spurred-India-to-design-own-GPS/articleshow/33254691.cms https://m.timesofindia.com/home/science/How-Kargil-spurred-I... This seems to have moderately more information. It seems like maybe they wanted to use GPS capabilities in their guided weapons systems, and the US would not permit it or perhaps threatened to disable the system in that theater? It’s a bit confusing and fuzzy.
- stedaniels 8y agoThere are many scenarios, but here's a simple one. Boots on the ground. You have men on the ground who can see the enemy position, they need to know exactly where they are to be able to know exactly where the enemy is. Without GPS you are relying on visual points of reference against maps of shaky providence.
- bluGill 8y agoBoots on the ground don't need to be accurate to within 1cm. If a normal human is within 10 meters they can nearly always figure things out. In fact if humans are that close it is because you don't actually know where the enemy is and you need the humans to find them - otherwise you would have a plane drop a bomb on them. Where you need more accuracy is when you want something at a long distance to do something - drop a bomb or something.
- michaelt 8y agoAs far as I can tell, all the online reports have been written 15+ years after the fact, and they all just quote one another; I suspect the journalists may be mistaken. It's worth bearing in mind the Kargil War took place in 1999, and GPS Selective Availability wasn't turned off until May 2000. It might be that India asked for the SA seed key so their own forces/missiles could navigate more accurately, but were denied?
- chiph 8y agoIIRC, with SA on, accuracy was to within 100 meters. And that's enough for troop movements but not accurate enough for missiles and artillery. So using it for land navigation would have been fine. It's sounding like it was a case of "We want it because we want it"
- rdsubhas 8y agoKargil is one of the highest battlefields on Earth. I don't think I'd compare Himalayan warfare to "land navigation". https://en.wikipedia.org/wiki/Kargil_War https://en.wikipedia.org/wiki/Kargil_War https://en.wikipedia.org/wiki/Mountain_warfare#Kashmir_conflicts https://en.wikipedia.org/wiki/Mountain_warfare#Kashmir_confl... > The most dangerous and volatile of all mountain conflicts involves the ongoing one between India and Pakistan over the Kashmir region.
- chiph 8y agoIt's a generic term meaning "How do I get my troops from here to there" either by vehicle or marching, such that they don't get lost and arrive when needed. This is the classic way with map + compass. GPS just makes it easier. https://www.youtube.com/watch?v=xSNohNPqWlU https://www.youtube.com/watch?v=xSNohNPqWlU
- SoulMan 8y agoAlso because swearing-in ceremony of Barack Obama as US President in January 2009 had a disastrous impact on the test-firing of the BrahMos supersonic missile https://www.thehindubusinessline.com/news/national/how-obama-swearing-in-scuttled-brahmos-missiles-test-flight/article23103459.ece https://www.thehindubusinessline.com/news/national/how-obama...
- sdhgaiojfsa 8y ago> But an apprehensive US official turned down the request and told Kalam: “Sorry Dr Kalam, we will give you good lunch and dinner, but no Craig computer.” > Kalam came back empty-handed, but went on to develop the Pace Plus computer with help from the Indian Institute of Science and others in two years. And, Pace Plus proved to be 20 times faster than Craig! This type of thing sounds incredibly childish and jingoistic to my American ears. Does it read better to folks who learned to speak English in India, or is it just really awful writing? Also, as best I can tell, there is no "Craig" super computer. Does the author mean Cray? And if so, why was the scientist asking the USG? You would normally want to get such computers from the manufacturer, not a foreign government, however friendly.
- dilawar 8y agoThat's the usual state of news reporting. People just love discourse of conspiracy over here.
- shripadk 8y agoIt's not a conspiracy. The sale of Cray supercomputers was indeed blocked by the US Government. Just because the article is badly written doesn't negate the facts on the ground.
- shripadk 8y agohttp://www.rediff.com/computer/dec/18super.htm http://www.rediff.com/computer/dec/18super.htm I agree that it is awful writing. I hope the article above is written better. > Does the author mean Cray? And if so, why was the scientist asking the USG? You would normally want to get such computers from the manufacturer, not a foreign government, however friendly. It's not possible to directly purchase from manufacturers if the US Government is going to block the purchase on various grounds. Don't forget that there was a period where sanctions and arms embargo was also imposed on India. It's a different thing that today the US considers India a "strategic partner" but it wasn't always the case. As far as Cray goes, they even setup an award in the name of the scientist mentioned in the article (who also served as the President of India from 2002 to 2007 [1]): https://www.cray.com/blog/cray-hpc-awards-honor-achievements-india/ https://www.cray.com/blog/cray-hpc-awards-honor-achievements... [1] https://en.wikipedia.org/wiki/A._P._J._Abdul_Kalam https://en.wikipedia.org/wiki/A._P._J._Abdul_Kalam
- inglor 8y agoGPS broadcasts several signals, the higher precision ones are encrypted - until 1999 GPS was encrypted at much lower resolution but the army and armies it shares its tech with still operate at a higher resolution. The US can lock countries out of higher resolution GPS at will - this (and GLONASS) make sense because of it.
- jhayward 8y agoI would speculate that India wanted access to the encrypted military GPS signal, which would have given them 10-1000 times more accurate guidance for precision weapons.
- rrrazdan 8y agoCase of typical uninformed journalism. The basic use would be independent and reliable GPS guided munition.
- igravious 8y agoGPS is the US system. GNSS is the generic term. The basic use is navigation (the N is GNSS). That capability can be used for both civilian and military purposes. Chances are that even though it will be used by the Indian military it will be used far more often for civilian purposes.
- rrrazdan 8y agoYes, my bad on the GPS/GNSS. Yet on the use cases for this, I don't think India would have ponied up the money for this if it wasn't for the military use. With GPS, Galileo, Beidou and Glonass, the civilian navigation problem is pretty much solved. Are you aware of a use case it is solving that the others aren't?
- adventured 8y ago> India took a firm decision on IRNSS in 1999 after the US government refused to share GPS data Given India's rising position in the world economically (they'll have the fifth largest economy in two years or so) and militarily, they'd have been crazy to not go forward with their own system regardless. That's particularly the case given India has a very complex position among all the powers, from the US to the EU to Russia to China. They're far less blatantly aligned one direction or another than the rest. Their general geo-political neighborhood presents wild security considerations. To be a fully independent power in the coming decades, they'll want to gradually acquire their own capabilities at most things.
- buildfailure 8y agoWhere exactly does it say this the reason to start working on the "system" ? Also what do you mean by "work on the system" ? Reason for who to start working on the system ?
- nradov 8y agoThe Indian government is probably also concerned that if the USA ever gets into a shooting war with China or Russia, the GPS constellation could be destroyed by anti-satellite weapons (or at least rendered temporarily inoperable by other means).
- coolspot 8y agoIf USA, China and Russia go to war with each other, there will be no satellites left. Not US', nor India's.
- yaochao 8y agoyet China has Beidou navigation system
- dingo_bat 8y agoNow I'm just waiting for GPS chip manufacturers to add support. Should increase resolution for those in the subcontinent :)
- s_dev 8y agoHow does this compare to the Americans GPS? Is it as good or was it designed with different constraints in mind?
- rrrazdan 8y agoAs good but works only in the Indian subcontinent and its neighbourhood.
- lifeisstillgood 8y agoThis is both amazing and sad. Amazing because its the emergence of (yet another) a space power, and amazing because it gives the world more and presumably healthy competition for a globally useful technology. Sad because "we built, planned, funded and launched this awesome technology because ... war" Humans. What a species.
- ulam2 8y agoWar is the mother of all inventions.
- igravious 8y agoTechnology tends to be value-neutral. The application of technology could be for evil or for good. To claim that the primary purpose of the Indian Regional Navigation Satellite System (NAVIC) is for belligerent activities is to claim knowledge of the intentions of the Indian government at the time of the system's creation. Couldn't it be just as likely or more likely that multiple positive and negative rationales were in play at the time? - reduced dependency on the US - chance to learn something for oneself - give boost to the Indian aerospace fields - home-grown navigational abilities for war but also for civilian use - pride, wanting to be seen as a global tech leader - any other number of things? I think it is amazing that we now have not one (US) but five (US, EU, CN, IN, RU) navigational satellite systems, two of which (US, RU) are globally operational and two more will be (EU, CN) by 2020. What interesting times we live in.
- cocoablazing 8y agoPrincipals of the Indian space program are on record stating the system was developed to assure access to GNSS during conflict. There is no mystery regarding the motivations of the Indian government in deploying this system.
- shripadk 8y agoIs that necessarily a bad thing? Protecting one's sovereignty is essential in this day and age.
- vardump 8y agoSo my phone can use these satellite navigation systems: U.S. GPS, Russian GLONASS, European Galileo, Chinese BeiDou and Japanese QZSS. I guess one more doesn't hurt, huh? It's curious how major powers all want to have their own satellite navigation systems. Edit: QZSS is a regional system, and not due to start until November 2018, yet my phone detected one of those satellites earlier about 2-3 weeks ago. Interesting, especially considering I'm nowhere near Japan. Unless, of course, it was a bug or some weird error case. Or maybe QZSS was doing some early testing?
- 215163831328308 8y agoIf you build your missiles to work using gps (as another poster pointed out), then you also want those to work if the US decides to not let you use the gps system.
- orf 8y agoHow can you tell which nav systems your phone can see?
- vardump 8y agoAndroid API provides this: https://developer.android.com/reference/android/location/GnssStatus.Callback.html https://developer.android.com/reference/android/location/Gns... https://developer.android.com/reference/android/location/GnssStatus.html https://developer.android.com/reference/android/location/Gns... You can also use apps like GPS Test [0], etc. They can tell it as well. QZSS is represented by square icon(s) in that app. [0]: https://play.google.com/store/apps/details?id=com.chartcross.gpstest&hl=en https://play.google.com/store/apps/details?id=com.chartcross... (not affiliated with them in any way)
- azernik 8y agoThese are essential national security assets, used for military purposes, and which a hostile (or even neutral) owner could turn off in case of war. The civilian use-case is a handy side benefit.
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- Marc_Bryan 8y agoIMHO, it's pretty useless compared to the current government and country's scenario. They better electrify the villages and provide better sanitation to the people rather then spending millions on mars, moon missions to prove their superiority! What a waste! It may stop working in a year or two like any of their indigenous inventions!! I'm not undermining any Indians, nor the way they work but as they are governed is by far the worst considering the current and past situations. No quality, no nothing.
- msravi 8y agoCurious. Do missile systems also lose track of their position midway through a flight like our phones? Are the receivers radically better than the ones in our phones? What happens if a missile loses its coordinates because of a bad signal? Does it just continue and keep track of its position based on the last known position or does it abort? If it cannot lock on to a GPS signal at the start of its flight, does it fail to take off?
- djsumdog 8y agoMissile have their own very complex on-board guidance systems that don't require GPS at all. Newer missiles might use GPS as an extra layer of calibration, but I doubt they rely on it and most likely discard it if it's way off (otherwise GPS interference could potentially jam a missile).
- rainbowmverse 8y agoThere's a wiki on the various ways to guide a missile: https://en.wikipedia.org/wiki/Missile_guidance https://en.wikipedia.org/wiki/Missile_guidance
- sannee 8y ago> Do missile systems also lose track of their position midway through a flight like our phones? Civilian grade GPS receivers are intentionally crippled to stop working above some altitude/speed limits. EDIT: It seems that the COCOM limits apply only after "1,900 km/h at an altitude higher than 18,000 m". However, looking at the ublox receivers as an example, they have to be explicitly configured to operate at aircraft-level speeds, which smartphones likely aren't.
- isostatic 8y agoMy iphone has picked up gps signals on short flights on several offasions, I have an almost flawless track on a flight from LGA to DCA, and on over the Mediterranean from Frankfurt to Lagos. The LGA to DCA one had a max speed of 461mph (average 322) and altitude of 23,400 foot, with maximum negative gradient of 67.7%. Maximum speed I've recorded overall (I've had the app open for 24,190 miles) is 673.3mph, and max altitude of 35,081 ft