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Nowadays,wireless sensor networks attracts more and more attentions in the front edge technology,which is appraised as one of the three future high-tech industries. Wireless Sensor Network(WSN) is short-range wireless network consisiting of densely deployed large number of sensor nodes with different specs and functiong.Each sensor node has ability of appereceiving,computing and communicating, they form a network through ad-hoc mode.The sensor node periodically collects environment data and sends processed data or information to sink.Sensor network can apperceive,inspect and gather the information of a given object or enviorment through wireless communication between each node.ZigBee technology,proposed by IEEE organization and ZigBee alliance,with the characters of low-complication,low-power,low-data-rate,and low-cost,is suitable to take on the task of building the wireless sensor networks.Thus ZigBee has an extremely important worth for reaserch.This paper analysed the basic theory of ZigBee technology and the building of ZigBee networks,combined with domestic sensor technology currently, the wireless sensor network system for environmental monitoring is made.The system is composed of sensor nodes,routing nodes,central node and the host computer monitoring the platform.The sensor network is consisted of sensor nodes located in the offices,the network is used to gather environmental variables including dust,CO2,temperature,humidity and O2,etc;each sensor node contains a liquid crystal display,key operation and 232 communication,each sensor node can be used not only as a wireless network node,but also as a separate sensor system;routing nodes are responsible for transmitting data,the nodes can greatly increase the distance of wireless transmission;the central node receives all datas sent by sensor node, then LabVIEW software on the host computer displays,analysises and storages all datas.We have completed a small ZigBee star network and mesh network structures, realized detecting the environmental parameters continuously, the measurement results of sensors are accurate and reliable. And the distance of wireless transmission has been measured actually,the result expected to meet the requirement.
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