Research And Implementation Of Train Positioning Technology Based On BDS And Map Matching Fusion

With the continuous improvement of rail traffic information level,railway as an important part of rail transit,the improvement of train operation control level has become an unstoppable trend.In the train operation control system,real-time acquisition of train positioning information is the key to ensure the safety of train operation.The accuracy and real-time performance of train positioning is the basic requirement of train positioning system.Map matching is used as a software correction method for train positioning error,which is added to the train positioning system to reduce the positioning error existing in the combined positioning technology,and t.hen improving the positioning accuracy of the train,which is of great significance to ensure the safe operation of trains.(1)Based on the analysis of the existing train location map matching algorithm,this paper proposes a kind of point-to-point and point-to-line hybrid based on the problem that the single map matching algorithm has large matching error and the algorithm is complex and the matching real-time performance is poor.The map matching algorithm combines the advantages of point-to-point and point-to-line map matching algorithms,and improves the real-time performance of the matching algorithm based on reducing the matching error of the single map matching algorithm.(2)Aiming at the problem that the train positioning receiver has large measurement error when the BeiDou satellite signal is occluded,a BDS/ODO train combination positioning method based on hybrid map matching algorithm is designed.In areas where satellite signals are interfered,the curve interpolation algorithm is first used to supplement the orbital electronic map data.Then,the train positioning data obtained by the combined positioning is filtered by the extended Kalman filter to reduce the measurement error of the positioning sensor.Finally,these data is matched to the actual track by the calculation of the hybrid map matching algorithm,and improving the positioning accuracy of the train.Through simulation analysis,the BDS/ODO train combination positioning method based on hybrid map matching improves the train positioning accuracy of the satellite signal better region and blind zone.(3)Combining BDS,map matching algorithm,vehicle terminal technology,wireless communication technology and geographic information system,a train positioning system based on BDS and map matching fusion is designed.Tests show that the system can be used as an auxiliary positioning tool for train positioning,which can improve the positioning accuracy of existing trains and remotely monitor the real-time position of trains.