Research On Coverage In Wireless Sensor Networks For Regional Security

In the recent years, due to its characteristics of low cost, low power consumption and high adaptability wireless sensor network technology develops rapidly, and has been widely applied to various fields, especially in military applications has been the world wide attention, and regional security is one of the important applications. How to reduce the redundant nodes, prolong the lifetime of the network combined with the characteristics and requirements of regional security in the premise of effective coverage, has always been the focus of this research direction,and a key problem to take wireless sensor network to application.In order to reduce the density of nodes and network cost, and improve the network lifetime, this paper firstly studies the node density of area coverage, trap coverage and barrier coverage in order to devide the monitoring area by three kinds of security level, and use different coverage mode in the area of different security level. Considering the actual needs of regionalsecurity, we established a wireless sensor network framework for regional security, and discusses coverage performance, routing mode and the energy consumption of this network as a feasibility study.Then this paper research further on trap coverage detection and repair, and propose a distributed trap cavity detection and repair methods. The method uses Delaunay triangulation and cluster gets empty shape, and then based on the weight of judgment node repair order. To avoid the various possibilities of arcsplicing resulting failure and effectively reduces the required number of additional nodes. The method is more effective to patching a large area of trap hole, which is proved by analyzes and simulation.Finally, combined with the background of actual terrain application, this paper put forward a topographic correction method based on the slope information in digital elevation maps to detect trap holes under the undulate terrain by constructing directional sensing model of sensor nodes. Based on this method, this paper studies further the influence of slope, aspect and node spacing on trap holes detection. The simulation result demonstrates the algorithm and provides reference for the deployment of sensor networks under the rugged terrain.