TOA Time Of Arrival
The reference point for signal arrival time, TOA (Time Of Arrival) is defined as the start point of a time slot. Used for LCS (LoCation Services), and similar to E-OTD (Enhanced - Observed Time Difference) in that the time difference of the signal arriving at different base stations is used to calculate the location of a mobile device. The difference between TOA and E-OTD is that no overlay network is needed for TOA. Mobile networks currently do not employ these procedures; instead cells are synchronized using a common timing reference.
