Railway Information Transmission System Based On Wireless Ad Hoc Network

Railway state information can ensure the train get in,stop,orbital transfer and other activities correctly.The system also can back up the railway state information.On the other hand,it can transmit the information when the main automatic transmission system broke down.The Ad hoc network transmission system based on ZigBee has the characteristics of fast layout and strong anti-destructive which can meet the application requirements of data acquisition,transmission and processing of railway state information near the station.ZigBee wireless ad hoc network combine the sensor technology,communication technology and computer technology together which has the capabilities of information collection,transmission and processing.This paper introduced the characteristics and application of ZigBee technology,and studied the characteristics and structure of ZigBee protocol.Based on the general design principle of communication and embedded system,the overall scheme of transmission system is designed.Through the construction of TI Z-Stack software support platform,the improvement of routing algorithm and the realization of communication protocol,the system networking scheme based on ZigBee protocol and mesh structure is realized.The routing algorithm is the core design for the ZigBee network layer protocol.Based on the traditional routing algorithm in ZigBee and the transmission characteristics of the railway information,the algorithm is optimized and improved to satisfiy the constraint requirement for the control node in the routing process.The improved routing algorithm takes the link quality as the link cost,satisfies the requirement of the constraint control node to achieve the minimum link cost as the best route path and reduces the network packet loss and the route cost,satisfies the demand of railway circuit information transmission design.Finally,the transmission system design was accomplished.