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How can a GPS receiver lose satellites that are still working?

A working satellite is only one end of a navigation system. Its radio signal still has to reach a receiver clearly enough to be used, and other emissions can interfere with that process. The distinction explains how a receiver can lose useful satellite information even when the satellites themselves have not failed.

3–5 min

Questions you could explore

  • What other explanations would you consider before blaming a lost position on deliberate interference?

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Engineering and inventions

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Your phone can work out where it is by listening to signals from far above Earth. But turning a signal's travel time into a distance also creates a clock problem: the receiver must account for its own timing error.

12–15 min
Engineering and inventions

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A message crossing an ocean can travel through glass fibers lying on the seabed. The light inside, the layers around it, and the equipment along the route each solve a different problem.

8–10 min
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Why does one pedal turn take you different distances?

Changing bicycle gears changes the relationship between your pedals and the rear wheel. The teeth on the chainring and sprocket help explain why the same turn of the pedals can produce a different distance along the road.

3–5 min
How can a GPS receiver lose satellites that are still working? | Speech Topic | speaking.app