A novel weighting method for multiple otdoa based positioning in 3GPP LTE system

Abstract

In recent 3rd generation partnership project (3GPP) long term evolution (LTE) cellular environment, multiple observed time difference of arrival (OTDOA) based positioning is possible by using lots of base stations for tracking user's location. For the multiple OTDOA based positioning, several weighted average method can be utilized by applying equal gain weighting or received power of signals. However, the typical weighting methods for multiple OTDOA do not consider the expansion effect of reference signal's time difference (RSTD) estimation error due to the geometry among eNBs and UE. Therefore, in this paper, we propose a new weighting method for multiple OTDOA based positioning in 3GPP LTE system. The proposed method applies a curvature of hyperbola equations as a weighting value. For the purpose, the proposed method includes an approximation of hyperbola's curvature which is based on the estimated location of user and RSTD. Also, the positioning accuracy of the proposed method can be gradually improved by iterative procedure. We verify that the proposed method can effectively improve the positioning accuracy. © 2016 ACM.