Ranging

Time of Flight Methods

The object's position can be determined by measuring the range to a number of objects at known locations. Range is usually obtained by measuring the signal's time of flight (TOF), but may also be estimated frmo the received signal strength (RSSI).

Types

There are five types of time of flight (TOF) based ranging measurements from which a position solution may be determined:

1. Passive ranging or time of arrival (TOA).
2. Time difference of arrival (TDOA) across transmitters or hyperbolic ranging.
3. Differential ranging or TDOA across receivers.
4. Double-differenced ranging across transmitters and receivers.
5. Two-way ranging.