Thread

1. gorgoiler · 1790191708 · focus · HN ↗

   Presumably when World War 3 kicks off the very first thing each adversary will do is knock out their opponents satellites? These are like flying lightbulbs that shine down usefulness from above, so step one is to cut the lights.

   Presumably-squared there is some kind of military backup to survive once the lights (GPS) go dark? Whatever that technology is, why hasn’t it proliferated into civilian life so that we all benefit from a resilient, non-GPS backup?

   Perhaps the answer is that every tank has a 10lb inertial navigation gyro or some other thingy in it as a backup, and the platoon around it uses the tank as a moving trig point? In that case I can see it being infeasible to deploy that for civilians.

   Perhaps-squared it’s just economics — GPS is cool and cheap now, so why burn profit margin on developing an alternative?

   1. tim333 · 1790249152 · focus · HN ↗

      You see a lot of real world stuff going on in Ukraine. They haven't knocked out GPS satellites but have local jammers. The missiles and the like can use a variety of alternative systems like inertial navigation and terrain matching. There are a couple of startups that make a box that can navigate with a camera looking down at the scenery for ~$1 or 2k.

      There are also about half a dozen rival GPS like satellite systems <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Global_Positioning_System#Similar_systems" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Global_Positioning_System#Simi...

      The location system in your phone often uses a resilient, non-GPS backup based on cataloguing the locations of WiFi routers. Not due to enemy action but your Starbucks having a building over it. There are two main systems, one from Google, one from Apple. It can make a noticable difference if you are playing something like Pokemon Go. The thingy can be in range with one system but not the other.

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