Design Of Wireless Network Train Environent Monitoring System Based On Linux And ZigBee

With the gradually development of communication, embedded and sensor technology, Wireless Sensor Network technology (WSN) is emerged. It has become one of the front fields to recerch.WSN consists largely of wireless communication sensor nodes to form a network topology. It can implement the data collection, data processing and the application of transmission. As a new development in modern information technology area, the WSN communication technology has a broading application.At present, with the high-speed, automatic and comfortable development of China railway, train compartment's comfort status has been gradually attentiond. To monitor the train compartment's comfort information has become an important management part. Therefore,the need of effective monitoring system to ensure the train comfort appears more and more urgent.Based on this, this paper designed a train environment monitoring system based on Linux technology and ZigBee wireless sensor network technology. Through the ways of data acquisition, storage and analysis,the system can accomplish monitor and record the temperature, humidity, air pressure and smog-density environmental informations,so that,the monitoring is portable,intelligent.First of all, this paper introduces domestic and international train environmental monitoring backgroud, and then analyses ZigBee technology based on the 802.15.4 IEEE in detail, such as the features, network topology, protocol stack architecture, network-building flowchart, routing algorithm and so on. To the train monitoring requirement, the paper also give a general design scheme of wireless monitoring system,which including a ZigBee-wireless-network module and a ARM-controller module.Then the paper give a brief introduction of the ZigBee-wireless-network module and ARM-controller module,and analyses each module's structure detailly. In view of each modules function,the paper completed the hardware and software design.The paper also designed a hardware platform of ZigBee wireless network nodes module. Through researching networking process and data transmission on the platform, the function of wireless sensor network node is tested.Meanwhile,the paper designed ARM-controller module hardware platform.Based on ARM microprocessor and Embedded operating system Linux, the paper designed ARM-controller's hardware and software,including hardware structure,hardware principle diagram, serial device driver program. By using MiniGUI as software platform, paper also designed a MiniGUI environmental-condition monitoring application program.Finally, the monitoring system network performance is test,test shows that, the network founds success, it can achieve multi-point distributed compartment environmental measurement.Distributed wireless measurement system can be easily laid to the specified train compartment with a strong scalability and mobility, easy to use.