Research On Self-Localization Algorithm In Wireless Sensor Networks Based On Power Control

Node localization is one of the basic technologies in many applications of wireless sensor networks. Without nodes'position, the gathered information is of little worth. In the wireless sensor networks, by controling the transmission power of node can affect energy consumption, localization performance and the topology of network. By studying the existing wireless sensor networks self localization algorithms, this paper proposing two localization algorithms based on power control for wireless sensor networks: one is Power-weighted Centroid Localization algorithm (PWC), another one is DV-Hop Localization algorithm based on Power Control (PDV-Hop). The main research works are as below:First of all, proposing a centroid localization algorithm based on power weighted: this algorithm is based exclusively on connectivity and uses power information of the beacon nodes as weight factor to calculate the estimated position of unknown nodes, whose power influences the result of centroid calculation. This algorithm can reduce the average locating errors and it is fit for mass wireless sensor networks application.Secondly, proposing a DV-Hop improved algorithm with power control: this algorithm improves the accuracy of estimated distance by power control, and the iterative numerical method with the initial values of estimated node locations was presented by setting proper threshold, thereby improving the localization precision.In the end, simulation experiments and performance evaluations are performed under Matlab7.0 simulation platform. Simulation results show that: for the ideal signal propagation model, PWC is applicable to the networks application that positioning accuracy is not high, but the higher network lifetime requirements; By increasing the node computation and communication overhead appropriately, PDV-Hop can improve the location accuracy significantly, and is fit for the networks application that high localization precision, but the communication overhead and network lifetime less demanding.