How Does GPS Work? | In Orbit | BBC Earth Science

The breakthrough technology that lead to GPS was a clock - but not just any old ticker. Satellite engineer Maggie Aderin-Pocock reveals how this jaw-dropping technology makes our lives run smoothly.

In Orbit: How Satellites Rule Our World (2012)
How the thousands of satellites orbiting the Earth have transformed the modern world.

[sbomorse]

I didn't realise that the Doppler effect was influential in GPS!

[Dani-itsy]

Of all the technical inventions of the modern era this is the most genius and helpful one. I remember so well driving in to the center of a metropol with a big lorry and a map on my lap 😱 Nightmares 😫

[tinytonymaloney]

Well i never, i always believed GPS was via geostationary satellite. That presenter is a very interesting person, she makes something quite complex look simple 👍

[devrim-oguz]

To be technically correct, the GPS doesn't use atomic clocks to measure how long the time takes to reach it. This is enabled by high-speed clocks. The atomic clock in the satellite is used for keeping accurate time for a long duration and for correcting the relativistic time shift caused by height from the earth.

[peterthomas]

So how does the GPS in my car know the time differential between the signal from the satellite and the time it's received at my car?
My car GPS doesn't have an atomic clock...

[murilo]

This woman was born to speak, godanm tha's a fine voice to listen to.

[foihdzas]

Isn’t the atomic clock crucial due to relatively, and the fact that a fast moving object (the satellite) is moving faster through space, and thus time, relative to the car/person needing location information? Meaning the satellite’s time moves slower than that of the surface of the earth?

[NyznTvfk]

minimum 4 because it's an equation of 4 unknowns : x, y, z for space and t for time.

[mdzaid]

It doesn't explains anything. In order to know our location, we should know location of the satellites. But how do those satellites maintain their position.

[petehiggins]

Actually it's more complicated than you would think because there is no atomic clock in the GPS receiver.

Do smartphones have GPS? Can they receive these timestamps from GPS satellites?