The Research And Realization Of ZigBee Wireless Sensor Network

In recent years, wireless communication technology developed rapidly. As a significant part of wireless communication technology, ZigBee has raised researchers’ attention with its low cost, low power consumption, low date transfer rate and high-security features. Now, ZigBee has been widely used in the areas of military, industry, healthcare and environmental protection.Although zigbee wireless sensor network has obtained lots of significant theoretical research results, the problems of deploying the real system still exist. In large-scale network, the traditional routing protocols are incapable of keeping the stability of the data transmission. The stability and life time of the network didn’t reach the expected requirement.The paper analyzes several important routing protocols in ZigBee wireless sensor network and summarizes the weaknesses of each protocol. The routing path is usually not the optimal one in Cluster-Tree routing protocol and it will lead to the network partition if one of the routers is malfunction. Although AODVjr protocol provides the optimal routing path for the arbitrary source and destination pair in the network, it requires the route discovery process for each communication pair. The route discovery overhead and the memory consumption proportionally increase with the extending of network scale. Moreover, the flooding mechanism wastes a large amount of bandwidth and device energy, and might cause a "broadcast storm" problem.The paper illustrates the realization of ZigBee wireless sensor network by introducing the project "Temperature and Humidity Monitoring and Control System Based on Zigbee Wireless Sensor Network", including the structure of ZigBee2007 stack, the mechanism of OSAL operating system, the working process of system and problems and solutions in the process of deploying the system, which include the low power consumption wake-up mechanism, the ZigBee node’s recovery mechanism and the extending mechanism of the network.At last, we propose a new routing algorithm called load-balanced shortcut routing protocol to solve the problems existed in the system, which include the following aspects.1) The routing path is not optimal.2) The method of selecting next hop node is inconsiderable, because we only considered the RSSI and neglected the factor such as LQI, the surplus energy, node’s nework depth.3) The hot spot issue in the network.