| ¡¡ | Chinese Journal of Computers Full Text |
| Title | The Energy Hole Problem of Nonuniform Node Distribution in Wireless Sensor Networks |
| Authors | WU Xiao-Bing CHEN Gui-Hai |
| Address | (State Key Laboratory for Novel Software Technology, Nanjing University, Nanjing 210093) |
| Year | 2008 |
| Issue | No.2(253¡ª261) |
| Abstract & Background | Abstract The nonuniform node distribution strategy can be used to mitigate the energy hole problem in wireless sensor networks. In this paper, the authors investigate the theoretical aspects of the nonuniform node distribution strategy in multi-hop wireless sensor networks, and prove that in a circular sensor network with nonuniform node distribution and constant data reporting, the unbalanced energy depletion among the nodes in the whole network is unavoidable. In spite of this fact, suboptimal energy efficiency among the inner parts of the network is possible if the number of nodes in the network is quantified and meets some conditions. The authors propose a novel nonuniform node distribution strategy based on their analysis and a routing algorithm coupling with the proposed node distribution strategy for achieving the suboptimal energy efficiency. Simulation results show that when the network lifetime ends, the inner coronas nearly attain balanced energy depletion. keywords wireless sensor networks; energy hole; nonuniform node distribution background In a multi-hop wireless sensor network, a subset of nodes behaves as both data originator and router. Data collected by nodes will be sent to the sink hop by hop. As a result, nodes nearer the sink always run out of energy and die earlier, leading to an energy hole in the network. No more data can be delivered to the sink and quite a lot of energy is wasted when the energy hole appears. The nonuniform node distribution strategy, i.e., adding more nodes to the traffic-intensive areas, is an intuitive way to tackle this problem. But whether this kind of strategy can thoroughly avoid the energy hole problem is not fully explored. The authors try to answer this question in this paper. The authors prove that although the energy hole can not be avoided in a network with nonuniform node distribution and constant data reporting, suboptimal energy efficiency is still possible. The authors propose a new nonuniform node distribution strategy and devise corresponding routing algorithm to attain the suboptimal energy efficiency. This work is supported by the National Basic Research Program(973 Program) of China under grant No.2006CB303000, the National Natural Science Foundation of China under grants Nos.60573131, 60673154 and 60721002, and Natural Science Foundation of Jiangsu Province under grants No.BK2005208 and No.BG2007039. The group has published highly selective research papers in the fields of wireless sensor networks, wireless mesh networks, and P2P systems.` |