Research Of High Speed Train Positioning Scheme Based On LTE-R

Since China’s railway industry got rapid development in recent years, the High-speedRailway has become a new card of the railway operations department. EMU trainbrought a convenient and comfortable environment for passengers. At the same time, the highspeed also proposed a new challenge to the railway operations departments of the safe andefficient.Accurately locate the real-time position of all train is needed by the railway operationsdepartments. The train positioning method of railway in traditional way includes circuit trackand the Balise, or the new way includes cross induction loop and spread spectrum wireless.Exist for these methods either point can not give real-time positioning or poor positioningprecision or low noise immunity. I proposed a special method that use mobile communicationnetwork by rail to high-speed trains wireless location. This method can positioningcontinuously and has a high positioning accuracy, cost savings and other advantages.However, wireless communication channel is uncertain, easy to interference to noise duringtransmission, multipath fading, path loss and other factors. These effects will lead the wirelesssignal parameter measurement inaccurate, then result positioning low accuracy. Therefore,how to design structures and processes positioning system is also a key element of this study.Therefore, this paper starts with the development trend of mobile communication fromthe high-speed railway, to research the high speed train positioning scheme based on LTE-R(Long Term Evolution for Railway). As the public4th generation mobile communicationsystem, LTE has the features of high data rate, good mobility, excellent quality ofservice, security. Its application in railway was named LTE-R has been introducing by theInternational Railway Union, would be a great progress of railway communication.This paper presents the method of high speed train positioning based on LTE-R. Themain idea is to get the train’s location use the wireless positioning method bythe railway’s mobile communication system. Wireless positioning is a method to measurethe radio parameters from a transmitting device to a receiving device, and then estimatestheir location. It mainly divided into the network positioning, the mobile positioning andthe auxiliary positioning by subject embodiment. And the measured parameters can bethe received signal strength, or the signal arrival angle method, or the signal arrivaltime method etc. Compared with public wireless positioning, train wireless positioning has itsparticularity, such as the train has its restriction by the rail, and the relationship between thelocations of base stations for positioning.The content of this paper is to introduce the existing train positioning method, and thedevelopment of railway’s communication system. To studies the LTE physical layer protocol standard. To describes the advantage of train wireless positioning. To analysis theparticularity of train’s positioning parameters choice compared to the public networks’, suchas the restriction from rail and the relation of positioning using base stations. The paper alsogives a specific train positioning scheme design, including the factors affecting thepositioning mode selection, the scheme’s structures and processes, and the mathematicalalgorithms about positioning parameter estimation and train’s position solver. Finally, use thesoftware MATLAB/Simulink to simulate the design scheme. The simulation workouts can beused to be reference for practical engineering application.