Design And Development Of Communication Gateway For Cultural Relic Environment Monitoring Systems

China has a long history and many precious relics,which is a symbol of China,so it is of great significance to protect them with morden science and tcehnology.Monitoring relics is an essential procedure of relic protection.It requires real-time and long-term monitoring.During the monitoring,human check is inefficient,assembling sensor is difficult,and the cost is huge.ZigBee wireless sensor network shows features over the traditional system,such as low cost,low power consumption,Ad-Hoc Network,short scale range,which is suitable for monitoring the environment of relics.Ethernet tech is capable to transfer data from a long distance,so it is essential to design a communication gateway for the communication between ZigBee network and Ethernet.In this thesis,the framework of environmental monitoring system is studied,and the communication gateway is designed and described for this purpose.The main contents are as follows.Through the participation in writing the Application Requirements for Network Communication of Cultural Relic Preservation Environment Monitoring System,the author designed the network communication protocol for environmental monitoring system,and separated communication procedure into four kinds.The message structure and related commands are designed,and the gateway communication state machine is designed according to the four communication modes.There is a complete design of hardware part of the communication gateway.The core processor of the gateway is i.MX287.The communication module of ZigBee is CC2530.The physical chip of Ethernet is LAN8720A.Combining three of them implements the connection between ZigBee network and Ethernet technology.For the convenience of test,there are also some surrounding circuit,such as power supply module and RS-232 serial port module.The gateway program is written and debugged,which mainly contains Ethernet communication and ZigBee communication.The communication protocol between ZigBee module and embedded system is designed,which means that ZigBee could send data to embedded system and embedded system could send task back to ZigBee.The communication between gateway and server is based on UDP protocol.The gateway data is packaged based on the network communication protocol for environmental monitoring system.Sending function with retransmission mechanism is designed,which selects communication mode state machine automatically according to communication command and completes the communication process.Finally,it is proved that the gateway design meets the requirement of applications,by testing and verifying the consistency of the communication protocol.