Research And Simulation Of High Speed Train Interated Positioning Method Based On GNSS/DR/LTE-R

With the continuous improvement of the speed of high-speed trains,the requirements of the railway operation department for the safe operation of trains have also increased accordingly.Train positioning is the key technology for train control system control the safe operation of trains and improve the efficiency of railway transportation.However,the traditional train positioning method relies too much on ground trackside equipment,which can not meet the needs of future train control systems for positioning.Therefore,this paper proposes a train integrated positioning method based on global navigation satellite system(GNSS),dead reckoning(DR)and LTE-R in combination with the development trend of next generation train control system and positioning requirements.The related information fusion algorithm is studied with the aim of improving the accuracy and reliability of train positioning.Firstly,this thesis describes the structure and positioning process of the train integrated positioning system,and studies the positioning principle and error model of GNSS and DR.According to the distribution characteristics of LTE-R communication base stations along the railway,the method of realizing train wireless positioning based on time difference of arrival(TDOA)measurement values and track line information and the process of solving train position are given.Secondly,aiming at the problem of low positioning accuracy and poor stability in the process of acceleration,deceleration and turning of trains,the information fusion algorithm based on interactive multi-model is studied,namely interactive multi-model volume Kalman filter(IMM-CKF).The information fusion algorithm based on interactive multi-model is studied.That is,interactive multi-model cubature Kalman filter(IMM-CKF).At the same time,in order to improve the fault tolerance of train integrated positioning,this paper combines interactive multi-model algorithm with federated filtering to study the information fusion algorithm based on federated interactive multi-model.Subsequently,the federated filter structure,fault detection and system reconstruction scheme were designed,and the system state model and measurement model of each sub-filter were established.Finally,based on the image user interface development environment provided by Matlab,the train integrated positioning simulation system is designed and implemented.And the positioning data provided by the simulation system is used to verify the performance of the information fusion algorithm.Through comparison experiments,it is found that the information fusion algorithm based on interactive multi-model can effectively improve the accuracy and stability of train positioning.In the case of GNSS or LTE-R failure,the integrated positioning system based on federated filtering can detect and isolate the faulty positioning subsystem in time,which proves that the integrated positioning system has strong fault tolerance.