To improve accuracy, OTDOA positioning must be used in conjunction with other methods, such as E-CID .
The standard LCS methods in LTE are E-CID, Assisted GNSS (A-GNSS), OTDOA (also referred to in LTE as downlink positioning), and UTDOA (also referred to in LTE as uplink positioning).
E-CID. As already stated in Sections 3.2 and 4.2, ECID enhances CID accuracy by adding reference data to the position fix, such as RSS levels (RSS levels can also be used to provide distance estimations in circular multilateration positioning ) and RTT values.
It supports E-CID, A-GNSS, and OTDOA, as well as hybrid localization to improve accuracy.