Time of Arrival

Time of Arrival ( TOA or ToA, German "Arrival Time ", sometimes also Time of Flight (ToF)) is the propagation time of a radio signal from a single transmitter to a remote single receiver . In the relationship between the speed of light in a vacuum and the carrier frequency of a signal, time is a measure of the distance between the transmitter and the receiver. However, some publications ignore the fact that this ratio is well defined for the vacuum but is different for all other materials when radio waves pass through them.

Compared to the Time Difference of Arrival (TDOA) method , ToA uses the absolute time of arrival at a certain base station instead of the measured time difference between sending at one station and arriving at the other, while the Frequency Difference of Arrival (FDOA) method uses it is to be delimited. The distance can be determined directly from the time of arrival because signals travel at a certain speed. ToA data from two base stations narrow the position to a position circle. Data from a third base station is needed to improve the exact position on a point. Many radio location systems such as GPS use ToA.

See also

• GSM localization
• Distance measurement
• Triangulation
• Trilateration

Individual evidence

1. ^ David Adamy: Ew 102: A Second Course in Electronic Warfare (online, Google Books ), 2004, p. 164.