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Why Is GPS Free?
- djaouen 3y agoI dunno. Why is fire free?
- caminante 3y agoI'd trust the wiki entry [0] over Reddit comments. [0] https://en.wikipedia.org/wiki/Global_Positioning_System https://en.wikipedia.org/wiki/Global_Positioning_System
- Animats 3y agoBecause it's one-way and predates the era of DRM. To charge for it (which the EU's Galileo system originally planned to do), you need a crypto system, secure modules in receivers, a key distribution and billing system, and customer service. That could end up costing more than providing the service.
- EscapeFromNY 3y agoAnd it would probably be reverse engineered anyway the same week the public got their hands on the receiver hardware.
- nimish 3y agoIf the M-code has been reverse engineered, then it's not public.
- Laremere 3y agoGPS had this capability, and it was turned off: https://en.m.wikipedia.org/wiki/Error_analysis_for_the_Global_Positioning_System#Selective_availability https://en.m.wikipedia.org/wiki/Error_analysis_for_the_Globa...
- toomuchtodo 3y agoSoft power from a public good > picking up pennies
- ApolloFortyNine 3y agoVery misleading comment, none of that section implies the government was selling access. They were limiting it so other militaries couldn't use it.
- fsh 3y agoThe high-precision P(Y)-signal and the new M-signal are still encrypted. This is essential for military applications since otherwise GPS would be trivial to spoof.
- netsharc 3y agoYeah, it would be like satellite TV, with each receiver having a unique key (well, each receiver has a card interface where one can plug in a card with a key. The satellite TV signal sends encrypted decryption keys and as long as you're a subscriber, the chip on your card will be able to decrypt one of those keys, which in turn can decrypt the encrypted broadcast signal. AFAIK originally the DoD weren't thinking of making GPS for public, just for military. Having these requirements would just make it extra complex, and unnecessary. First, it would require a lot of bandwidth, and then yeah, a bottleneck for how many receivers can be deployed, and it could take a lot of seconds until a unit finds a matching key to decrypt. Imagine a soldier needing to wait for her equipment to get the key to find her location while in a firefight...
- vlovich123 3y agoWasn’t SA killed because the algorithms defeating it became widely known and thus there wasn’t really any point to it?
- jrockway 3y agoNear the end of SA people did figure out how to minimize its influence. Not because they could decrypt the military code, but because of differential GPS (compare the raw signals you receive with the raw signals at a known location called a continuously operating reference station; the reference station didn't move, so if the signals said it did, that's how wrong they are in that particular corner of the earth) and the ability to solve the navigation equation based on the actual carrier phase/doppler shift instead of only the transmitted messages. Both of these techniques are still good for removing much of GPS's error, which mostly involve the uncertainty about the "speed of light". It changes locally as the total electron content of the ionosphere changes. Measure against a reference station or between two different radio frequencies (L1/L2C), and that error can be minimized. You don't need a reference station anymore, as things like WAAS try to transmit these corrections from a satellite. If you want to play with high-precisions GPS, you can easily buy fancy u-blox modules from Sparkfun, connect them to a Windows computer running uCenter (from ublox), and get access to reference stations through your state to do full DGPS. With good sky conditions, you should be able to move your receiver a few centimeters and watch the lat/lon change accordingly. (New York State's service is here: https://cors.dot.ny.gov/ https://cors.dot.ny.gov/. It's free! They use a software suite that's designed to charge customers money for using the data, but the prices are all set to $0.) People say that the achievement of the 20th century was the Internet, but I think GPS was a lot harder. The Internet is just computers connected to each other with cables! This is atomic clocks in space sending you messages indistinguishable from noise that let you find your position in space within a centimeter. When the aliens invade, I think they'll be impressed! I am, anyway.
- vlovich123 3y agoYup I was talking about differential GPS. As for difficulty, both are achievements and don’t undersell the difficulty of networking. At the 500ft level it’s all just wires but the actual details of doing it are incredibly difficult. It’s just that we’ve had so much experience pushing it forward that there’s a lot we can just take for granted which removes the magic from it. https://www.allaboutcircuits.com/news/ethernet-turns-50-look-back-feats-robert-metcalfe-co-inventor-of-ethernet/ https://www.allaboutcircuits.com/news/ethernet-turns-50-look... And that’s just local area networking. Networking broad area networks is even more complicated. As for people calling it the achievement of the 20th century, it’s more because of how it made the world smaller and the network effects of the changes it’s wrought to society (and from that perspective it is bigger than GPS and the computer itself).
- moffkalast 3y agoFundamentally because supporting one receiver costs the same as supporting an infinite amount of them, the rest is politics.
- amelius 3y agoIf the fundamental part of your argument played any role in medicine, then all the >$1M cancer treatments would be practically free too.
- SnowHill9902 3y agoPharmaceutical companies are not charging for the cost it took to develop that drug, but for the rolling cost it’ll take to develop future ones.
- schwartzworld 3y agoAlso CEO bonuses
- jeroenhd 3y agoNot necessarily, incredibly large amounts of money pharmaceutical companies spend is actually spent on advertising their products to maintain their cash flow. Examples can be found online but this source [1], which is obviously biased, shows the statistics for the biggest companies in a nice list. The (hundreds of) millions spent on bonuses are nothing compared to the billions spent on making sure your doctor recommends UmbrellaCorp PainAWay™ over a generic brand that will cost you a tenth of the price [2]. That includes not just TV ads, but also buying conference tickets and free lunches for doctors; anything to make sure they get the upper hand. [1]: https://www.csrxp.org/icymi-new-study-finds-big-pharma-spent-more-on-sales-and-marketing-than-rd-during-pandemic/ https://www.csrxp.org/icymi-new-study-finds-big-pharma-spent... [2]: It should be noted that some generics can work less effectively or cause additional side effects in some people, but for many types of medication the difference is minimal and sometimes the big-brand products even come with more side effects than their competitors' product
- Simulacra 3y agoI'm surprised no one has mentioned that the a reason it's free is that people will use it. If people had to pay for it then they might not leave it on, or use it as much, and as a result a lot of the mobile apps that harvest location data would be affected.
- acchow 3y agoFull-precision GPS has been open for public use long before location-tracking apps were invented.
- Simulacra 3y agoBut that doesn't mean the ability to receive that signal cannot be monetized. If it could be monetized I reason someone has considered it
- chiph 3y agoAs mentioned above, the costs to distribute keys, manage accounts, deal with customer service, etc. would be high. The Galileo system apparently considered it at one time.
- jrockway 3y agoFrom reading the thread, I have a question that maybe HN knows the answer to. I feel like I haven't had to do a cold start on new GPS chips in a really long time. Even in terrible sky conditions, I've never had to wait 12 minutes to download the almanac. Do chips just ship from the factory with this data, or is it not needed anymore. (I know about AGPS, but that's not involved. This happens on receivers with no possible way of communicating to the outside world other than the serial port I'm reading navigation messages from.) Even if I do a reset + cold start in u-center or similar, I still don't have to wait 12 minutes. I wonder why.
- fh973 3y agoIt may have flash. Parts of the AGPS data are valid for weeks and may help the cold start.
- deleted 3y ago[deleted]
- robinduckett 3y agoDrone GPS chips on FPV quad copters still need significant time to acquire satellites (several minutes)
- throw0101b 3y ago> Do chips just ship from the factory with this data, or is it not needed anymore. While the general orbits of the satellites (each is uniquely identifiable) can be pre-shipped, orbits do fluctuate, so the data would still need to be updated / fine tuned. > The receiver is missing or has inaccurate estimates of its position, velocity, the time, or the visibility of any of the GPS satellites. As such, the receiver must systematically search for all possible satellites. After acquiring a satellite signal, the receiver can begin to obtain approximate information on all the other satellites, called the almanac. This almanac is transmitted repeatedly over 12.5 minutes. Almanac data can be received from any of the GPS satellites and is considered valid for up to 180 days. * https://en.wikipedia.org/wiki/Time_to_first_fix https://en.wikipedia.org/wiki/Time_to_first_fix But a general fix can do done without any initial data, and is sped up by being near the previous last fix and caching some data.
- mensetmanusman 3y agoHistory: America puts it up to help target ICBMs, etc. US taxpayers/military give it away for free as a gesture of good will which also has political benefits.
- JumpCrisscross 3y ago> America puts it up to help target ICBMs Modern ICBMs use GNSS. Historically, they didn’t. Certainly not when the GPS constellation was deployed.
- philipkglass 3y agoModern ICBMs use GNSS. Do they? The US hasn't deployed a new generation of ICBMs since the GPS constellation became operational. I would also expect that plans for nuclear war wouldn't rely on vulnerable satellites remaining operational. I thought that US weapons used GPS guidance as a low-cost alternative to other guidance methods in forgiving environments that don't have electronic warfare countermeasures (e.g. fighting the Taliban or armed forces equipped with old gear).
- whartung 3y agoGPS is important to the military, but many modern combat systems can get along without it. Most systems that use it have some manner of backup. GPS in combat debuted during the Gulf War, but mostly as a backup for navigation rather than targeting. We did not have 100% coverage back then, all of the satellites were not up yet.
- AstralStorm 3y agoYou did have 100% coverage back then, but not high quality all of the time. In some rare cases only a single satellite pseudofix would have been available. That can still be accurate if the location device carries a decent synchronized clock. IOC was defined as always being in sight of 3 or more satellites, plus maintenance capability. That was achieved in 1993.
- ianburrell 3y ago
- avalys 3y agoThought one: wow, the fact that this was asked on a subreddit called "Ask Historians" really makes me feel old. Thought two: I've never considered how bizarre it is that GPS is an enormously expensive satellite constellation launched and maintained by the United States military that we make available for free to the entire world. As a US citizen I take it for granted - but it must be strange for someone to grow up in (for instance) Lebanon and use a GPS device.
- AstralStorm 3y agoIt was a very calculated decision - it made the others rely on US tech dominance, with the moment someone gets too uppity the P(Y) and M code encryption, and Selective Availability noisy mess on normal code gets turned on and only USA plus some advanced multiband tracking receivers get accurate location... For good 30 years the strategy generally worked so much that satnav got synonymous with GPS. Big players launched their own constellations anyway. GLONASS, Beidou and fledgling but accurate Galileo. And there are still more systems. So if GPS wasn't free manufacturers would use something else.
- sbierwagen 3y agoI'd say the calculated decision was making it available to civilians in the first place: >After Korean Air Lines Flight 007, a Boeing 747 carrying 269 people, was shot down by a Soviet interceptor aircraft after straying in prohibited airspace because of navigational errors,[42] in the vicinity of Sakhalin and Moneron Islands, President Ronald Reagan issued a directive making GPS freely available for civilian use, once it was sufficiently developed, as a common good. That's the neutral phrasing on Wikipedia. The actual announcement: https://www.reaganlibrary.gov/archives/speech/statement-deputy-press-secretary-speakes-soviet-attack-korean-civilian-airliner-1 https://www.reaganlibrary.gov/archives/speech/statement-depu... >In their recent statements on the Korean Air Lines tragedy, senior Soviet officials have shocked the world by their assertion of the right to shoot down innocent civilian airliners which accidentally intrude into Soviet airspace. Despite the murder of 269 innocent victims, the Soviet Union is not prepared to recognize its obligations under international law to refrain from the use of force against civilian airliners. World opinion is united in its determination that this awful tragedy must not be repeated. As a contribution to the achievement of this objective, the President has determined that the United States is prepared to make available to civilian aircraft the facilities of its Global Positioning System when it becomes operational in 1988. This system will provide civilian airliners three-dimensional positional information.
- aynyc 3y agoI tho it’s paid for by American general tax. Is it not?
- chiph 3y agoIt comes out of the US Space Force budget, so yes. https://www.spaceforce.mil/About-Us/Fact-Sheets/Article/2197765/global-positioning-system/ https://www.spaceforce.mil/About-Us/Fact-Sheets/Article/2197...
- bentobean 3y agoIt isn’t free. You paid for it. We all paid for it.
- lr1970 3y agoGPS is owned by US government and operated by US military [0]. And US military does not charge retail :-) [0] https://en.wikipedia.org/wiki/Global_Positioning_System https://en.wikipedia.org/wiki/Global_Positioning_System