this post was submitted on 03 May 2024
322 points (98.5% liked)
NonCredibleDefense
6608 readers
1091 users here now
A community for your defence shitposting needs
Rules
1. Be nice
Do not make personal attacks against each other, call for violence against anyone, or intentionally antagonize people in the comment sections.
2. Explain incorrect defense articles and takes
If you want to post a non-credible take, it must be from a "credible" source (news article, politician, or military leader) and must have a comment laying out exactly why it's non-credible. Low-hanging fruit such as random Twitter and YouTube comments belong in the Matrix chat.
3. Content must be relevant
Posts must be about military hardware or international security/defense. This is not the page to fawn over Youtube personalities, simp over political leaders, or discuss other areas of international policy.
4. No racism / hatespeech
No slurs. No advocating for the killing of people or insulting them based on physical, religious, or ideological traits.
5. No politics
We don't care if you're Republican, Democrat, Socialist, Stalinist, Baathist, or some other hot mess. Leave it at the door. This applies to comments as well.
6. No seriousposting
We don't want your uncut war footage, fundraisers, credible news articles, or other such things. The world is already serious enough as it is.
7. No classified material
Classified ‘western’ information is off limits regardless of how "open source" and "easy to find" it is.
8. Source artwork
If you use somebody's art in your post or as your post, the OP must provide a direct link to the art's source in the comment section, or a good reason why this was not possible (such as the artist deleting their account). The source should be a place that the artist themselves uploaded the art. A booru is not a source. A watermark is not a source.
9. No low-effort posts
No egregiously low effort posts. E.g. screenshots, recent reposts, simple reaction & template memes, and images with the punchline in the title. Put these in weekly Matrix chat instead.
10. Don't get us banned
No brigading or harassing other communities. Do not post memes with a "haha people that I hate died… haha" punchline or violating the sh.itjust.works rules (below). This includes content illegal in Canada.
11. No misinformation
NCD exists to make fun of misinformation, not to spread it. Make outlandish claims, but if your take doesn’t show signs of satire or exaggeration it will be removed. Misleading content may result in a ban. Regardless of source, don’t post obvious propaganda or fake news. Double-check facts and don't be an idiot.
Join our Matrix chatroom
Other communities you may be interested in
Banner made by u/Fertility18
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
GPS is a product of the US military; its usefulness to them would be limited if it were North America only, since they mostly wanted it to tell where they were, wherever they happened to be in the world that they had no knowledge of but were actively fuckin' with.
GPS is equally available to civilians in Freedomland as it is to civilians wherever else in the globe. They used to arbitrarily fuck up the signal resolution for the non-military version, until they realized that all they were doing was (a) mildly inconveniencing tech companies who had go through the rite of passage of assigning a single junior programmer to determine how to mostly undo their resolution-fucking-with which wasn't that challenging (b) motivating every other country to develop their own GPS equivalents.
By the time they just let everyone have real GPS, people had cottoned on to the idea that maybe putting your navigation under the whims of the US military wasn't a great idea, and had gone to the pretty significant expense of developing their own. So now there's a bunch of them, and you can pretty much choose whichever one pleases you. But with the exception of NavIC, they're all available all over the world.
wait gps is unscrambled niw? then why is it still so inaccurate?
If you have a modern receiver, like any smartphone from the last 10 years, gps is accurate to a couple of meters.
It’s only a couple of meters for a few of reasons: necessity, speed, and scale.
It’s not necessary for most users to have centimeter precision for gps. Most uses for GPS is for humans to find a place, most humans have eyes, or can at least read braille signs. So if you’re looking for a pizza place and your gps says you’ve arrived, you can look around and see that the pizza place is 3 meters down the road.
Speed, because you can get really accurate locations out of gps, but your receiver would need to refine your location by talking to many satellites many times, which isn’t needed for most users as just knowing if you’re on the right street and the right side of the street is enough. Many communications would mean it takes a long time for the gps device to determine a precise location, which is frustrating for your average user.
And scale, it’s a really big planet, and there’s a finite number of gps satellites. The less satellites in your network, or the less they’ll talk to your receiver, means less accurate data and a less accurate location.
TLDR: most people don’t need sub meter precision from their gps, so it’s simply not provided to most people.
How inaccurate are we talking? Selective availability used to fuzz location by 30 meters which is insane.
This species is getting spoiled
The main limitation now is actually the atmosphere. As the air heats and cools, it expands and contracts. This changes the amount of air the signal is passing through. Since the speed of light in air is slightly slower than vacuum, the effective position accuracy is reduced.
There is a fairly simple correction, you need a static reference. If you have a fixed receiver, then pass its readings to the dynamic one, then you can correct for errors. Combined with inverse kinematics you can get sub centimeter resolution quite reliably.
This page explains the reasons and seems pretty credible (and also gives a date for the descrambling; it was fixed as of May 2000).
In what way is it inaccurate? Google maps can locate you within a couple of meters.