Mobile Node Localization Design Of Wireless Sensor Network

Localization technology for node in Wireless Sensor Network is one of the supporting technologies which are to estimate unknown nodes to neighbor distance or number, using the information exchanged between the nodes to determine their position in the network. According to whether measuring the distance between nodes, it could be divided into range-based localization algorithm and range-free localization algorithm. Range-based localization algorithms need high hardware cost and high energy consumption, and localization accuracy depends on the density of anchor largely in the network, so the range-free and mobile anchor node localization is the development trend of today.In this thesis, it gives a detailed introduction to Wireless Sensor Network localization algorithm proposed by now. It mainly embodied in following aspects: After analyzed the range-based localization algorithm and range-free localization algorithm, and mainly focusing on the range-free algorithm of localization Range-free algorithms of localization include Centroid, DV-Hop, Amorphous and APIT localization. Four range-free localization algorithms by matlab simulation in the same environment, and get node deploy diagram, neighbor diagram, and localization error diagram. The paper compared the advantages and disadvantages of range-free algorithm of localization from localization accuracy, network size, node density and density of anchor nodes. The simulation results indicated that each localization algorithm has its own of the environment, so we should choose the appropriate localization algorithm in different occasions.In order to overcome the limitations of static localization algorithm, the paper analyzes the mobile anchor node localization algorithm, and this localization mechanism reduces the cost of netwoik construction, and reduces the influence of the surrounding environment on the localization accuracy in a way. The paper introduced the Monte Carlo Localization and Particle filter. The method of inserting directly and least square was used in the motion model of mobile anchor node. Finally, the paper simulation maximum likelihood method and Particle filter method by using matlab simulation platform, and estimate the trajectory of the mobile node's average tracking error.