Design And Realization Of Locating Terminal For Train Monitoring System Based On Beidou/GPS

Transportation industry has always been the most important part of the national economy and life.With the continuous expansion of China's railway construction investment,China's railway construction has entered a period of vigorous development,the capacity of railway carrying,size and speed have been greatly improved,high-speed train construction has been in the forefront of the world.With the expansion of the scale of the railway,the speed and the density of the operation increases,the safety of rail transport is becoming more and more important now,how to ensure the safety and reliability of railway transport is of great significance.For this situation,an important part of a train monitoring system for high-speed trains was been designed and implemented in this paper:Beidou/GPS positioning terminal.This paper first analysised the demand of the train monitoring system,and combined with mature embedded technology,designed a high-reliability,high integration,low-cost train monitoring system.In the aspect of hardware,embedded chip TM4C series has been used as the core,and it carried out the relevant schematic design and chip selection work.The schematic design is in introduced by each module,which mainly included power supply circuit,processor circuit,serial circuit,memory circuit,positioning module circuit and so on.In the aspect of software,the state machine thinking has been adopted.The Beidou/GPS positioning terminal software part is divided into five sub-tasks:Beidou communication message processing task?located message processing task?serial data processing task?power down processing task and LED processing task.According to the demand,working principle and the scommunication process of these sub-tasks has been detailed.At last,this paper tested the system function and performance of the Beidou/GPS positioning terminal.After builded a test environment,the Beidou/GPS positioning terminal function has been tested.Tests have been shown,the Beidou/GPS positioning terminal which designed in the paper has achieved three modes of positioning?storage and communication of Beidou short message based on Beidou Satellite.It met the train monitoring system for the Beidou/GPS positioning terminal functional requirements and environmental needs fully.