LTE Fingerprinting Localization with Altitude

The paper shows how to add altitude to the adaptive enhanced cell identity (AECID) fingerprinting localization method in the long term evolution (LTE) cellular system. This improves the precision of E- 911 emergency positioning in vertically extended regions like in tall buildings. The altitude is added to the corners of a polygon using assisted GPS (A-GPS), observed time difference of arrival (OTDOA) or uplink time difference of arrival (U-TDOA) altitude measurements of opportunity. A new algorithm transforms to a 3-dimensional point with an ellipsoidal uncertainty, since the latter format is standardized on all LTE position reporting interfaces.