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.
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/
https://oceanservice.noaa.gov/education/tutorial_geodesy/geo09_gps.html