Research On Localization Algorithm For Wireless Sensor Network

Wireless sensor networks, which integrate technologies of micro-electro- mechanism, sensing, embedded computing, distributed information processing and wireless com-munication. Wireless sensor networks, as a brand-new technique in information acquisition and processing, can be widely used in many areas such as national defense, environmental supervision, medical treatment, outer space exploration, counter-terrorism and disaster retrieval. It is considered as one of the most important techniques of the 21st century.Localization, which has been focused as a basic problem, is the precondition of many applications of sensor networks, such as target identification, surveillance and tracking. Existing localization algorithms can be roughly divided into two categories:range-based localization algorithm and range-free localization algorithm.The research of this thesis is based on the analysis of the self-localization algorithms on wireless sensor networks and its main structure include:First of all, the research status of wireless sensor localization techniques and positioning systems for wireless sensor networks are summarized based on the study of a lot of related literatures. In this thesis, the criterion of performance evaluation and algorithms, the taxonomy for wireless sensor networks localization systems are described, the principles and characteristics of recent representative localization approaches are discussed and presented.Secondly, on the base of the centroid algorithm and the bounding box algorithm, it designs a new localization algorithm by integrating into the opening operation idea of the mathematical morphology and the tow hop theory, and discusses its core ideas and algorithms. In this thesis, by enhancing the complexity of the centroid algorithm and using all the sink node convergence to different range and direction after processing the opening operation, a presented centroid algorithm based on the opening operation reaches the aim of reducing localization error. The algorithm of Bounding Box based on the two hop information makes use of the information of anchor nodes within the scope of two hops, and increases the constraints conditions of unknown node, and reduces the potential region of the unknown nodes, so this algorithm achieves the objective of improving the positioning accuracy. Then, we should simulate and analyze two algorithms using MATLAB, the method is feasible and effective by simulation analysis, However, two algorithms will appear on the phenomenon on the enlarging positioning error in some local location, but taking into account this small probability of the special problem, so improving the network nodes of the positioning accuracy will not have an effect.Finally, we have given a conclusion and put forward the future on the localization technology of wireless sensor networks in the last paragraph.