The Study On Range-Free Node Localization Algorithm Of Wireless Sensor Networks

Wireless sensor networks (WSN) is a new researching topic concerning the micro-electromechanical, embedded computing, distributed information processing and wireless communication technique. The WSN is reputed as one of the top promising technologies in the coming decade. The WSN research includes several fundamental areas, i.e. node localization, topology controlling, routing protocol. Among them, the node localization is the precondition of the WSN target cognition, in-network-monitoring as well as the object tracking. Based on those issues, nodes localization technique is crucial topic in WSN research.The sensor node has strict restriction on the unit volume, unit cost and energy capacity, and the sensor nodes always works in the unmanned scenario. Considering the above characteristics of WSN nodes, it is impossible to directly using the standard wireless localization mechanism on WSN. Instead, it is necessary to develop specific node localization algorithm for WSN application. Our paper introduces the related theory and presents the WSN node localization technique.By comparing the existing WSN localization algorithms, considering the particular characteristics of WSN nodes and the requirement of application, we propose an improved algorithm based on DV-HOP. The algorithm utilizes the reverse routing tag mechanism to label the shortest path, reduces the size of in-computing node set to improve the accuracy. Also, we introduce a anti-calibration factor to minimize the error, so as to efficiently localize the unknown nodes.The simulation results confirm our algorithm can accurately localize the target faster than the DV-HOP. Our algorithm provides a reasonable reference mechanism for WSN research and application.