Target Tracking Technology Based On Trajectory Prediction For Wireless Sensor Networks

Target tracking keeps an important research area in Wireless Sensor Networks.As a widely used technology,it has many distinctive characteristics of large scale,high energy consumption,wide application,etc.Under this circumstance,many researchers not only concentrate on the research of tracking accuracy,but also try to find out an optimal design of network construction,route prediction and low-energy consumption.In order to enhance the accuracy of target tracking,and to reduce the delay as well as energy consumption of network,a type of energy-efficient target tracking approach(ETTA)is proposed in this thesis.Details of ETTA are described as follows.Firstly,in the thesis,the irregular monitoring network area is divided into “grids”,and sensor nodes are organized as “clusters” according to the related rules.The nodes in clusters cooperate with each other to achieve the exact position of target,predict the moving path and track it in real time.At the same time,a node sleep-scheduling strategy is established.The nodes which don't participate in target tracking enter into sleeping mode to reduce energy consumption and prolong network lifetime.Secondly,by improving classic RSSI and APIT,a more accurate location algorithm is proposed in this thesis.The exact position of target can be detected even if surrounding nodes are of sparse distribution.In order to enhance the robustness and fault-tolerance of the target tracking system,many scenes have been taken into consideration and analyzed accordingly.For example,whether the target can be found timely by nodes when it is at the boundary or even out of the network,how to predict the moving path of target or track it in real time.Thirdly,some unavoidable accidents usual y occur during the process of tracking such as target missing.Therefore,a tracking recovery mechanism is proposed in this thesis that can effectively prevent target missing and re-locate the target promptly after the target was lost.The adverse consequences caused by target missing are reduced greatly,and the stability and scalability of the target tracking system is improved obviously as well.