Pseudo-range multilateration

Pseudo-range multilateration, often simply multilateration (MLAT) when in context, is a technique for determining the position of an unknown point, such as a vehicle, based on measurement of biased times of flight (TOFs) of energy waves traveling between the vehicle and multiple stations at known locations. TOFs are biased by synchronization errors in the difference between times of arrival (TOA) and times of transmission (TOT): TOF = TOA − TOT. Pseudo-ranges (PRs) are TOFs multiplied by the wave propagation speed: PR = TOF·s.

Source: Wikipedia — Pseudo-range multilateration (CC BY-SA 4.0)