Research Of Indoor Precise Positioning Technologies Based On TD-LTE System

With advances in technology and the increased demand for human life, people’s requirements for mobile location services have already surpassed the E-911standards of the cellular networks wireless location technology published by U.S. Federal Communications Commission (FCC). Mobile location Services are not only used for emergency positioning, but for more diverse aspects. This year, telecommunications operators in china will actively carry out the construction of LTE network, technologies of positioning based on TD-LTE will become a hot topic, especially for indoor scene in where GPS can not work.Firstly, this paper describes the development of wireless location technologies and rearch of TD-LTE location, expounds all kinds of positioning technology principle and implementation plan in LTE. On this basis, OTDOA positioning method is selected to be main object of TD-LTE indoor positioning study. And the paper detailed analysis the main problems in the implementation process of this method.Secondly, based on the results of previous studies, this paper discusses two issues (How to ensure accurate time synchronization between base stations and how to get downlink RSTD parameters accurately) that affect the accuracy of OTDOA indoor positioning. And use IEEE1588protocol and downlink delay estimation algorithm to solve the issues.Then, this paper uses Wirless Insite software and WINNER channel to build a indoor positioning simulation platform, which simulates the indoor propagation environment of a shopping mall, and implements the proposed positioning scheme in the platform. The simulation results illustrate that the proposed scheme is feasible and very effective.In addition, as the probe for other methods not included in TD-LTE protocol, this paper implements the fingerprint positioning method in TD-LTE positioning system. The paper analyses the main factors that influence the accuracy of fingerprint positioning method through some simulations. Then it proposes a feasible scheme for indoor fingerprint positioning based on TD-LTE system, and demonstrate the scheme is valuable as well. Finally, this paper compares the two proposed positioning schemes, summarizes the advantages and disadvantages of the schemes and the future research directions.