Inhomogeneous Distribution Strategy Based on Mobile Sink Nodes in Wireless Sensor Networks

Energy consumption equilibrium is of great significance for the wireless sensor networks . For a circular sensor network, nonuniform node distribution strategy can be used to avoid the energy hole around the sink. However, it will potentially result in unbalanced coverage because the only central sink node will cause more nodes deployed in the inner region than the outer. Based on mobile sink nodes, an inhomogeneous distribution strategy is proposed to improve coverage quality. To deploy the nodes, the whole network is divided into multiple adjacent coronas as unit interval. Obviously, the number of corona is equal to the radius of network. The number of nodes in the network ascends from the second corona to the outermost corona with geometric proportion, while the ratio is kept constant between different coronas. With mobile sink node deployed on the edge of network, a calculation model of node sensing and coverage is adopted to evaluate the coverage quality. Furthermore, energy consumption model is used to improve energy efficiency. Experimental results show that our algorithm can achieve suboptimal energy efficiency and make 99.5 % coverage rate of the whole network, which outperforms the traditional nonuniform node distribution algorithm to a great degree.