LTE Location Based Services Technology Introduction White paper
LTE Location Based Services (LBS) involve the process of determining where a device is located. Global Navigation Satellite System (GNSS) based solutions are highly accurate and the technology of choice for absolute position accuracy, providing the device has a good line-of-sight, but this is not always the case. A device can be in a highly dense urban environment with reduced satellite visibility or indoors with very low signal levels.
These limitations of GNSS systems have meant that LTE cellular based alternatives have been developed within 3GPP Release 9 and onwards.
They are described in this white paper.