Path Planning For Mobile Anchor Based On Regional Strategy

In recent years,the theory and knowledge for Wireless Sensor Networks(WSNs)has been improved with the further research and development.There is a growing number of related applications adding to the daily life.Many pratical applicationds for WSNs require the ordinary nodes to know their own specific locations,therefore nodes localization is an very inportant key technology for WSNs.Currently localization algorithm based on anchor for WSNs is widely used for nodes localization,localization algorithms based on anchor can be divided into two categories according to whether the anchors can move.As the mobile anchor compared to the static anchor has many advantages in localization,many scholars focus on the localization algorithm based on mobile anchor.Because the path of the anchor has a significant impact on the nodes localization,the path planning for mobile anchor has also became the hotspot for research.Existing mobility models or anchor mainly include random mobility models and non-random mobility models.There are always many repeated paths and the problem of low efficiency for localization in these mobility models.To solve these problems and shortcomings,this paper proposes two novel path planning algorithms for mobile anchor,Path Plan Algorithm based on Relative Coordinates(PPARC)and Path Plan Algorithm based on Local Relative Coordinates(PPARLC),with the research and analysis of the existing knowledge.In these two algorithms,anchor decides its own direction and speed of the movement according to the relative coordinates of the normal nodes,which can solve the problems such as excessive repeated paths.In PPARC algorithm,anchor plans its own movement trajectory according to the relative coordinate origin and edge nodes.The simulation results show that PPARC algorithm can ensure high location precision and coverage in the area with high destiny of nodes,and its movement distance is much less,compared with SCAN and HILBERT.PPALRC divides the entire network region into a number of local regions firstly,then the mobile anchor determines its path for traversing the entire network region dynamically,according to the local coordinate information and the number of nodes.The moving of anchor belongs to random mobility model.The simulation shows that the algorithm can also have high location precision in the region which the nodesare distributed unevenly.Compared with other path planning algorithms,it can ensure most nodes be located with small moving distance,and the movement distance for traversing the entire network region is shorter.