FCC chair says we’re too dependent on GPS and wants to explore ‘alternatives’.

[xanza@lemm.ee]

Having functional GPS in a tunnel would be very nice

In a tunnel

a tunnel

tunnel

I fear for the world. You afraid that you're gonna make a wrong turn? Inside of a tunnel? A fuckin' tunnel my guy?

[wjs018@piefed.social]

You have clearly never driven on 93 through Boston where the person you replied to said they are from (aka the Big Dig). It is basically an entire highway that is underneath the city. There are many on and off ramps, lanes suddenly become exit only, complex multi-lane exits that branch...it's intimidating. As somebody that has lived in the Boston area for 15 years now, I still mess things up.

[notfromhere@lemmy.ml]

Oh boy, where do I even start? This comment is wrong in multiple ways. Let's break it down:

1. "The way triangulation works is by essentially measuring distance."

   • Nope. This describes trilateration, not triangulation.
   • Triangulation uses angles, while trilateration uses distances. GPS works via trilateration.

2. "1 satellite distance puts you anywhere in a radius (circle) of that satellite."

   • Kind of, but missing a crucial detail:
     • A single satellite defines a sphere around itself (not just a circle—you exist in 3D space).

3. "2 Satellites puts you at 1 of 2 locations where those radiuses intersect."

   • Wrong. Two satellite distance spheres intersect to form a circle, not just two points.

4. "3 satellites gives you a single location."

   • Mostly right, but incomplete.
   • In theory, three satellites narrow it down to two possible points, but one is often out in space or somewhere unrealistic, so it can often be ruled out.
   • However, because your device lacks an atomic clock, it typically requires four satellites to synchronize time properly.

5. "That's why it's called triangulation. Tri = 3"

   • Nope. GPS does NOT use triangulation.
   • The "tri" in triangulation comes from angles, not the number of satellites. GPS uses trilateration, which is based on measuring distances, not angles.

Final Verdict

This comment is a trainwreck of incorrect terms and flawed explanations. If they meant "trilateration," at least part of it would make sense, but calling it "triangulation" completely ruins their credibility.

So, in short? No, their comment is very incorrect.

[ulrich@feddit.org]

A single satellite defines a sphere around itself (not just a circle—you exist in 3D space).

You are not getting a 3 dimensional location. That's why GPS coordinates only exist on 2 planes. You don't know what you're talking about.

[saik0shinigami@lemmy.saik0.com]

You are not getting a 3 dimensional location. That’s why GPS coordinates only exist on 2 planes. You don’t know what you’re talking about.

Coordinates on a circle is a 3 dimensional location. The earth isn't flat.

[leeks@lemmy.world]

You are so close to VOR!

[splinter@lemm.ee]

They’re describing LORAN.

[abidanyre@lemmy.world]

There was an article today about how they just used GPS on the moon.

[ulrich@feddit.org]

The earth isn't flat.

So which coordinate accounts for elevation? Latitude or Longitude?

[dubyakay@lemmy.ca]

Don't need GPS to track phones. You triangulate the receivers.

[rizzrustbolt@lemmy.world]

Whatever happened to radio ranging?

That shit was super coolio.

[t156@lemmy.world]

It's also just a generally bad idea to be too dependent on a single system. If GPS reception fails for one reason or another, it would be good idea to have a backup.

[t156@lemmy.world]

Its like the video showing firefighters struggling a lot to break the window of the Tesla pickup. That's not a prasieworthy thing. You want the windows to break easily enough you can get out in an emergency, or someone can break in to get you out.

[rottingleaf@lemmy.world]

That would be wise.

[rottingleaf@lemmy.world]

One can use both and anything else frankly, isn't it enough to triangulate the signal between 3 satellites (or 2 with an interval and knowing their trajectories relative to each other) and match the spot on the geoid's (stored model, position precalculated by time) surface?

[rottingleaf@lemmy.world]

It’s also just a generally bad idea to be too dependent on a single system.

You're saying this in the world where SMS is considered good for 2FA, and PSTN identifier is considered as good as your citizen's ID, and people's lives depend on systems incorporating NodeJS and Kubernetes. Yeah, by the way, Docker everywhere, and all the POSIX standardization and source-compatibility to allow different systems adhering to standards ... have lost to Linux just becoming another main target.

But yes! It's a bad idea. Also it's typical now for these systems to start lying in warzones where their owners don't want one of the sides to have satellite navigation. They then give shift maps or whatever to the side they want to win.

[800xl@lemmy.world]

How do we call these assholes and tell them to get their heads out of Muskovitch's ass?

[lengau@midwest.social]

There's no reason why some sort of augmentation system couldn't improve the navigation situation with the big dig. Stick some low power beacons that provide GPS-like signal in the tunnel based on their predetermined location and we'll have GPS accounting for special relativity, general relativity and continental drift.

[gwilikers@lemmy.ml]

Is that the difference between when something like Google Maps has your general location and when it has your specific location?

[0x0@programming.dev]

Starlink is LEO, GPS is not.