I live in an area with a lot of iron. I cannot trust a compass to always point north. Generally I’ve had no problems in the woods: follow the trails that are on the maps, or at least stay close enough that you can always find them again and you are fine. (until of course you are not)
Phones already do that with cell towers. It’s called A-GPS (augmented GPS). Cell towers, wifi, and even bluetooth, are used in addition to GPS/GLONASS/Galileo signals.
Satellites project a sphere, you need 4 in order to get to a singular point. I’ve outlined each step. Fourth isn’t for clock correction only. And even outlined why sometimes 3 is okay, but that requires additional logic that many gps devices sometimes can’t compute, and even outlined that the vast majority of devices will use way more than 4.
Oh boy, where do I even start? This comment is wrong in multiple ways. Let’s break it down:
“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.
“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).
“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.
“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.
“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. 🚨
Satellites broadcast a sphere, not a circle. And that sphere doesn’t land on the earth as a perfect circle for relatively obvious reason… since the ground isn’t perfect flat, nor is the earth perfectly spheroid.
So… maps?
Time to bust out the compass.
I live in an area with a lot of iron. I cannot trust a compass to always point north. Generally I’ve had no problems in the woods: follow the trails that are on the maps, or at least stay close enough that you can always find them again and you are fine. (until of course you are not)
Triangulation could be more efficient than GPS, in terms of energy use and such
Triangulation of what, exactly? GPS already triangulates your position based on what it receives from multiple satellites, yeah?
Cell towers, in an urban area you’re typically within range of a couple.
Triangulation of GPS signals is what allows the System to determine your Position Global(ly)
Phones already do that with cell towers. It’s called A-GPS (augmented GPS). Cell towers, wifi, and even bluetooth, are used in addition to GPS/GLONASS/Galileo signals.
Is that the difference between when something like Google Maps has your general location and when it has your specific location?
A-GPS works faster than GPS on its own.
GPS literally triangulates your position using 3 satellites. It’s how it works.
No, you need 4 minimum.
Two satellites intersection places you on a circle. (all points possible)
Three satellites intersection places you on two possible points.
The last satellite give you the exact location.
However, the 4th can be omitted if one of the 2 points is not in a sane location. (eg well below the crust). And it’s trilateration not triangulation.
The reality is that your phone/device will use like a dozen satellites.
three sats determine your accurate position. the fourth is for clock correction only.
No.
Satellites project a sphere, you need 4 in order to get to a singular point. I’ve outlined each step. Fourth isn’t for clock correction only. And even outlined why sometimes 3 is okay, but that requires additional logic that many gps devices sometimes can’t compute, and even outlined that the vast majority of devices will use way more than 4.
https://gisgeography.com/trilateration-triangulation-gps/
https://www.gps.gov/multimedia/tutorials/trilateration/
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Deleted your comment because you looked at the last image?
Edit: The images on the site depict the exact thing I’ve been referencing.
1 satellite = whole sphere of options.
2 satellites = a whole circle of options
3 = 2 points
4 = 1 point.
Uhhh nope, that’s incorrect.
The way triangulation works is by essentially measuring distance.
So 1 satellite distance puts you anywhere in a radius (circle) of that satellite.
2 Satellites puts you at 1 of 2 locations where those radiuses intersect.
3 satellites gives you a single location.
That’s why it’s called triangulation. Tri = 3
Oh boy, where do I even start? This comment is wrong in multiple ways. Let’s break it down:
“The way triangulation works is by essentially measuring distance.”
“1 satellite distance puts you anywhere in a radius (circle) of that satellite.”
“2 Satellites puts you at 1 of 2 locations where those radiuses intersect.”
“3 satellites gives you a single location.”
“That’s why it’s called triangulation. Tri = 3”
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. 🚨
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.
Final Verdict
You’re not just wrong, you’re wrong AND you’re a dick about it.
Coordinates on a sphere is a 3 dimensional location. The earth isn’t flat.
Edit: Please education yourself before you’re so confident in your own bullshit answer. https://gisgeography.com/trilateration-triangulation-gps/ and https://www.gps.gov/multimedia/tutorials/trilateration/
Satellites broadcast a sphere, not a circle. And that sphere doesn’t land on the earth as a perfect circle for relatively obvious reason… since the ground isn’t perfect flat, nor is the earth perfectly spheroid.
So which coordinate accounts for elevation? Latitude or Longitude?
They should use that in GPS! /s