Design Of Wireless Environment Monitoring And Positioning System Based On ZigBee

With the popularity of intelligent networks and the continuous renovation of technology,wireless sensor networks(Wireless Sensor Networks,WSN)play an important role in people’s living standards and work efficiency.Aiming at the problems of traditional wired environment monitoring,such as complex wiring,high power consumption and difficult maintenance of equipment,a wireless environment monitoring and positioning system based on ZigBee is proposed.The further research of wireless location is doing while monitoring environment to improve the accuracy of environmental monitoring combined with location algorithm.WSN is widely used in robot,coal mine,underground parking lot and other living services in modern buildings because of its low power consumption,low rate,low cost,high reliability,time delay short and large network capacity and other advantages.Firstly,the present situation and key technology of wireless sensor network and wireless location are described in detail.Then,this paper analyzes the platform of hardware and software,the working principle and structure,ZigBee protocol and IEEE 802.15.4 standard,ZigBee network equipment and its topological structure,system performance requirements and various typical positioning methods.The ranging method by using RSSI signal loss to estimate the node distance is proposed.The free space propagation model,double line ground reflection model and logarithmic normal model are also used to analyze the signal attenuation characteristics.At the same time,the wireless means is used to monitor the environment,and the collected data is uploaded to the host computer and the mobile phone to realize the functions of accurate location and real-time monitoring of the environment.Finally,the 12 groups of RSSI values were collected in the laboratory and corridor.Using Fourier and exponential two different methods for fitting and discrete analysis these values by MATLAB,to obtain the corresponding fitting curve and residual analysis in two different environment respectively.By analysis,the closest to the real value of exponential fitting is educed,and then analyze the monitoring environment test.Respectively,the temperature and gas collection experiments,humidity and infrared acquisition experiments,both host computer and mobile phone are synchronized to display the environmental data,the reliability and stability of the system is verifed.