Research Of Train Wire Less Positioning Technology Based On LTE-R

In recent years,the development of C hina's railway industry is clear to see,all forms of rail transport have shown a momentum of rapid development.Railways have always played an important role in the rail transportation system,and is an important infrastructure and one of the most widely used means of transport,and it is also an important part of the existing transport system.Therefore,efficient and safe operation of the railway system has positive significance to the economic development of the whole society.In the process of train operation,obtaining the information of train location on the line timely and effectively is an important prerequisite for the safe operation of the train,so reliable and efficient train positioning method is very important.C ircuit track,the Balise,cross induction loop and so on belong to the traditional method of train positioning,which have some disadvantages like poor positioning precision,inability to provide continuous real-time information and high maintenance costs resulted from installation of trackside equipment.Some new positioning methods,such as position estimation method,GPS and so on have been put forward,which also have disadvantages like bigger cumulative error,susceptible to interference and high cost,therefore these new positioning methods can not completely solve the problem of train positioning.To overcome the drawbacks above,a new wireless train positioning approac h based on the railway private mobile communication network is proposed,Which can locate continuously and make full use of the existing network resources to save positioning cost.In view of the different working environment of the station and interval operation,different positioning approach need to be designed.In addition,high accuracy decoding algorithm is also an important research content of the thesis.Firstly,the thesis introduced the most widely used train positioning technology and the characteristics of wireless location technology,and studied the basic knowledge of the long term evolution(LTE)related to the position.Secondly,the thesis designed positioning process for the station and interval respectively combined with the specific situat ion of the railway traffic,and the Newton iterative method was applied to the calculation of the positioning solution.Thirdly,in order to make full use of the characteristics of railway line,a new automatic identification algorithm based on maximum lik elihood Hausdorff distance was proposed.Finally,the thesis simulated the scheme with MATLAB,the simulation results show that this approach can satisfy continuous positioning requirement of the train.