Design And Implementation Of WSN Positioning System Based On ZigBee Technology

Wireless sensor network is an emerging sensor network,it integrates theembedded computing technology,modern network and wireless communicationtechnology and so on which makes us more convenient to perceive the word.TheZigBee technology which based on IEEE802.15.4is widely used in industrialwireless positioning,smart home and so on because of its low energy,low cost,highreliability and other characteristics.Wireless sensor positioning technology gets moreand more attentions of researchers for its great significance in the mine,parking lot,fire danger in the environment of fire.This thesis which based on theanalysis of the existing positioning technology completes the improvement of thelocalization algorithm based on RSSI and the design of the wireless sensor networklocalization system on the basis of ZigBee.First of all,the thesis introduces the basic knowledge of ZigBee wirelesscommunication technology and systematic analysis the packet pormat and the mainfunction of reference model about the physical layer,the MAC layer,the network layerand the application layer of the ZigBee protocol stack systematicly,and then analyzesand compares the advantanges and disadvantages of several common short distancewireless communication technology. Then the thesis studies the wireless sensorpositioning technology;several typical localization algorithm about the needing andranging from distance measurement;the calculation method of three kinds of nodecoordinates；several typical localization algorithm MATLAB simulation comparison.Secondly,the thesis analyzes the inferfection of traditional based on RSSIorientation,and improves the algorithm aimed at the defects,there are mainly twoaspects:one is revising the measured distance between anchor node and blind nodethrough optimizing the RSSI values by use of Gaussian filtering;the other iscalculating the blind node coordinates by means of using the werghted factor ofcentroid location algorithm.Then the essay compares the simulation of localizationalgorithm before and after by use of the MATLAB simulation software.The resultsshow that the improved algorithm obviously improve the accuracy of localization,but the positioning time also increased.Finally,the thesis builds a wireless positioning system on the basis of RSSI basedon TI company’s CC2430/CC2431as hardware plateform.The main work of thisthesis includes:analyees the transplantation of protocol stack and networkingequipment of ZigBee;achieves the hardware composition of gateway node,anchornodes and blind nodes based on the hardware of CC2430/CC2431.analyzes thesending and receiving process of date the gateway node,anchor nodes and blind nodesin the system in detail and completes the software designs of each node;tests andobserves the buiding system which used the Z-Location Engineer monitoringsoftware as the epistasis software and achieves the good location effects.