Research On Coverage In Wireless Sensor Networks

With the development of information technologies, it is possible to integrate the computing, communication, networking and sensing into one tiny embedded device. Wireless sensor networks (WSN) is a new research area embedded of those technologies. Integrated with sensor unit, data processor unit and communication module, tiny sensor nodes can work to form a self-organization network, to sample the environment data or monitor the environment. The research of the wireless sensor network gradually gets the focus from the industrial and academe. It has a great application future in the military and civil area.This paper has a deep research on the coverage problem of WSN. Based on the analyses of coverage problem research progress and priorities, this thesis researches two important coverage problems: node self-scheduling coverage and k-coverage.This paper analyses an existed algorithm for node self-scheduling. The nodes' working time in every bound decided by a random time reference point. The algorithm limitation is that server time of node is changeless; it can induce some nodes run out of energy quickly. New algorithms that change the server time of node for every bound base on its remaining energy and produce more random time reference point are presented. Simulation shows that the proposed algorithms can balance energy consumption among nodes, prolong the networks server time and enhance the coverage quality under different deployment scene.Based on research of k-coverage and nodes division, a new algorithm for k-coverage based on disjoint subsets division is proposed and the detail of this algorithm is presented in this thesis. The proposed algorithm deals with the problem of node-choosing effectively. The disjoint division model makes it quickly and smartly to realize the k-coverage request. The experimental results demonstrate that the proposed algorithms achieve more subsets than random node-choosing model.