How does a GPS system determine speed?

What method does a GPS system use to calculate speed?

Is the accuracy of speed calculation influenced by special and general relativity effects?

Calculation Method:

A GPS system calculates speed by tracking the change in your position over time, using signals from at least four satellites.

Relativity Effects:

Yes, a GPS system takes into account both special and general relativity effects to maintain high accuracy in speed calculation.

A GPS system calculates speed by tracking the change in your position over time. GPS relies on 24 satellites orbiting Earth, with at least 4 detectable from any location on the planet. Each satellite is equipped with a high precision atomic clock.

The GPS receiver detects signals broadcasted from these satellites and calculates your position based on the time it took for those signals to reach you. The system is designed to account for relativistic effects such as special relativity and general relativity to ensure accurate speed calculation.

Special relativity is taken into consideration due to the high speed at which the satellites travel, while general relativity is factored in because of the weaker gravitational force experienced by the satellites in their orbits. Failure to consider these effects would result in a rapid loss of accuracy in GPS speed calculations.

Therefore, by tracking changes in position over a specific time period and applying fundamental principles of physics, a GPS system can calculate speed with great precision.