Connected k-Coverage Topology Control for Area Monitoring in Wireless Sensor Networks

One of the design challenges in Wireless sensor network (WSN) is to save limited energy resource to prolong the lifetime of the network without affecting their communication connectivity or sensing coverage . In dense WSN, the sensing areas of sensor node may overlap with each other. In general, the larger the overlap of the sensing range, the more redundant data will be generated with more energy consumption. In WSN, connected dominating set (CDS) has been used for energy efficient topology control, where a virtual backbone is formed, which allows communication between any arbitrary pair of nodes in the network. Nodes which are not in CDS can go to sleep state for energy conservation. Applications related to security and reliability require a certain amount of active nodes to ensure desired level of coverage at all time. These active nodes should be connected to reduce the delay during the communication. Therefore, it is necessary to construct a fault-tolerant CDS that continues to function during node or link failure, for both coverage and connectivity requirements of WSN. In this paper, we propose k-coverage connected dominating set (k-CCDS) for connected area coverage. We also propose a weight metric named weighted coverage cost (WCC), which consists of energy of sensing neighbors. The proposed protocol selects a CDS based on WCC to ensure that every non-dominating node is connected with the CDS even if k-1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$k-1$$\end{document} dominating nodes are dead. This CDS is named k-CCDS, in which every non-dominating node is covered by atleast k dominating nodes. Simulation results show that it performs better when comparing with A3Cov in terms of CDS size, coverage, energy consumption and lifetime of the network.