Research On Localization Algorithms For Mobile Nodes In Wireless Sensor Networks

Localization is the precondition of many applications of wireless sensor networks, such as target identification, surveillance and tracking. The application of the wireless sensor network technology is being more extensive as the research on it is getting deep, and the stationary network architecture can’t server the newly demand any more. Then, the mobile node is introduced in order to expand the application of wireless sensor network, but it brings the technology challenges as well. Currently, the localization of mobile node in wireless sensor networks has become one of the hot research problems.In this thesis, the research situation, the performance evaluation and the basic characteristics of wireless sensor network are systematically summarized, and then the location algorithm for indoor locating system and calculation method of the node position in the wireless sensor network are detailed studied. Localization algorithms are analyzed and compared in the existing and typical indoor locating system. The multilateral localization algorithm of Cricket localization system is been proved to be in high applicability for mobile node location.As far as ill-posed problem of mobile node positioning equations in wireless sensor networks is concerned, Tikhonov regularization method is adopted in this paper and the regularization parameter is taken by325. And the method is verified to be effective to improve the localization accuracy of the mobile node within8centimeters by MATLAB simulation results. On this basis, autonomous mobile robot is designed, combining with the Cricket indoor location system. A positioning system of mobile robot is built based on wireless sensor networks and also locating and tracking of mobile nodes is achieved in the indoor environment. The Experimental results show that Tikhonov algorithm combined with mobile robot has a good ability to be real-time and to adapt to the environment. And the locating and tracking of moving targets can be completed in laboratory conditions.