Location Research Based On ZigBee Wireless Sensor Network

With the rapid development of sensor technology, wireless communicationtechnology and distributed computer technology, the wireless sensor network with theoutstanding characteristic of low power consumption, low cost, large scale has beendeveloped rapidly. Wireless sensor network is composed of a large number of tiny sensornodes with wireless communication and computation ability in the form of multiple hopsand is praised as one of the most influential IT hot technologies in the21st century.Both in military defense and civil field, the location of the sensor nodes isparticularly important for the application of wireless sensor network. So the nodepositioning is the key technology for wireless sensor network. The node location can beobtained according to the minority nodes (reference node) whose position is known in thisnetwork and a certain location algorithm.The content about the features of the ZigBee communication technology, the protocolstack architecture and the main function of each layer are represented through a flood ofliterature. Then the paper studies several typical localization algorithms of ZigBeewireless network and discusses their advantages and disadvantages. The DV-Hop is themain research object among these localization algorithms in this paper for its extensiveapplication. To solve the problem that the hop value in traditional DV-Hop algorithm can’trepresent the real distance so as to cause significant error, an improved DV-Hop algorithmbased on RSSI is proposed. It mainly makes use of RSSI to correct the hop value from twoaspects. Simulation results show that the location accuracy of improved DV-Hopalgorithm is obviously increased compared with the original algorithm without additionalhardware.After comparing the characteristics of several kinds of ZigBee chips, CC2530chipembedded8051kernel is selected as the core chip to design wireless positioning hardwaresystem including the gateway node, reference nodes and unknown nodes. The systemsoftware for each node is developed on the Z-Stack protocol Stack of TI and the PCinterface of the positioning system is developed by VC++. Finally we do the location experiment in three surroundings: the corridor, the hall andthe playground. The environmental parameters are firstly measured in each scene and thenthe location data collected is analyzed by PC. Finally the location result is displayed onthe PC interface.