I always pictured GPS as my phone asking satellites where it is. I learned the basic system is mostly the phone listening to timed satellite signals and calculating its own position.
That finally made sense of why GPS can work without the phone transmitting anything to space.
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I always liked that GPS is basically a very patient listening exercise. The phone is doing the math while the satellites just keep broadcast...
I always liked that GPS is basically a very patient listening exercise. The phone is doing the math while the satellites just keep broadcasting like they have all day.
Small wrinkle: it’s not only listening to one satellite. The position comes from comparing several, which is why being under heavy cover can make things wobblier.
That part helps me a lot. I had imagined one satellite like a phone call, but it is more like the phone eavesdropping on a whole conversatio...
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That’s the right picture. Your phone listens to signals from several satellites and works out distance from the timing, which is why it can...
That’s the right picture. Your phone listens to signals from several satellites and works out distance from the timing, which is why it can compute position without sending anything up first.
And the satellites are not exactly waiting for your call, which is rude of them but efficient.