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First of all, a large number of relevant literate have been read, the development process of UWB positioning technology is introduced, and the common positioning methods of trains are summarized. It is found that the traditional train positioning technology is based on track circuit, transponder, etc., which has the problems of high cost, difficult maintenance, easy to be affected by the line, etc, Train-ground communication network provides great convenience for train positioning method based on wireless communication technology. Compared with several wireless positioning technologies, UWB positioning technology has high positioning accuracy and relatively low cost, so it is very feasible to use UWB positioning technology for "Skyrail" positioning.Secondly, the characteristics of UWB signal and the basic principle of positioning technology are described, and the common positioning methods are introduced, the advantages and disadvantages of various positioning methods and the main sources of positioning errors are analyzed, according to the actual needs, the location method based on TDOA is selected. Three algorithms commonly used in TDOA are simulated and analyzed: Chan algorithm, Taylor algorithm and Fang algorithm. Simulation results show that Chan algorithm is very suitable for "Skyrail" positioning.Then, on the basis of Chan algorithm, the relationship between location accuracy and base station location is determined by GDOP. For the scenario of "Skyrail" parking lot, the influence of different base station distribution and number of base stations on location is analyzed, tshe simulation results show that when the base stations are symmetrically distributed, the Chan algorithm has higher positioning accuracy for the whole parking lot, and the positioning accuracy increases with the number of base stations.Finally, Kalman filter algorithm is introduced for the "Skyrail" in the moving state, the Kalman filter algorithm based on TDOA measurement value and Chan algorithm based on Kalman filter are analyzed, and compared them with Chan algorithm. In the process of analysis, the relevant "Skyrail" motion model is established, and the base station distribution on both sides of the "Skyrail" running on the long straight track is designed, the simulation results show that the positioning accuracy of Chan algorithm based on Kalman filter algorithm is obviously better than the other two algorithms.