Zigbee-based Wireless Sensor Networks, Environmental Monitoring System To Study

With the rapid development of digital communication and computer network, many theories and standards of short-range wireless communication have been presented. From the initial GSM, Bluetooth to the Wi-Fi, the human even can not live without wireless networks. Especially the born of ZigBee promote the development of WSN (wireless sensor network). WSN is composed by lots of sensor nodes which have identical or different functions, and these sensors can auto-network. WSN based on ZigBee fills in the blank of low cost, low power waste and low transfer rate network, thus more and more people love it. For the needs of environmental monitoring, an environmental monitoring system is designed based on ZigBee wireless sensor in this dissertation.First of all, this dissertation analyses the ZigBee stacks, and particularly introduces the data frames of each layer, the address assignment of networking and routing theory. Further, the type of network device and topology are introduced.Secondly, the CC2431 is chosen as the central control module for wireless sensor nodes, and sensor nodes include air pressure, vibration, temperature and humidity. Based on this, the hardware of sensor network is built, and the debugging of hardware is completed.Thirdly, the software platform of simple environmental monitoring system is designed. And stacks of network layer and application layer are implemented, such as networking, joining of nodes, nodes'separating from network and data transmission. Network node software is designed; network formation and dynamic maintenance are completed.The WSN environmental monitoring system designed by this dissertation has characteristics of efficient networking, low energy consumption, low production costs, high reliability, and security. Hence, it can satisfy the need in different environment.