LTE user equipment RSRP difference elimination method using multidimensional scaling for LTE fingerprint-based positioning system

Currently, with the rapid development of 4G, most urban outdoor areas have been well covered with LTE signal, which provides the possibility to use LTE on land for positioning navigation system as a substitute of global navigation satellite system (GNSS). Because of cost and implementation difficulty, Minimization of Drive Tests (MDT) was proposed in LTE Release 10. It utilizes the LTE user equipment to feedback the measurement report of reference signal receiving power (RSRP) for the network optimization, which makes the LTE fingerprint-based positioning system possible. However, due to the mobile diversity, user habit and complicated channel, the user equipment (UE) RSRP difference is a non-ignorable problem that affects the positioning accuracy both in the online phase and offline phase. Therefore, in this paper, we propose an UE RSRP difference elimination method based on Multidimensional Scaling (MDS) algorithm. By using the relative RSRP difference between each two mobile terminals, we eliminate the RSRP difference both in the offline phase and online phase. We implemented the proposed method in a dense urban area and evaluated its performance. The experiment results indicated that the proposed method could effectively eliminate the UE RSRP difference and improve the positioning accuracy for LTE fingerprint-based positioning system.