Optimal Distribution of Redundant Sensor Nodes for Wireless Sensor Networks

Distribution of redundant sensor nodes has significant influence on the lifetime of wireless sensor networks. Firstly, layered network architecture based on regular hexagonal cells (RHCs) is introduced. Then, taking cells as the minimum working units instead of sensor nodes, optimal distribution of redundant nodes is investigated so that network lifetime can be prolonged as much as possible. Based on the analysis of network lifetime, redundant nodes multiple matrix R and probability density function f(k) are obtained as the optimal distribution conditions, which are used to distribute redundant nodes. Finally, simulation analysis has been conducted on the networks with the same architecture but the different distributions (optimal, uniform and Poisson) of redundant nodes. The numerical results show that network with optimal distribution of redundant nodes has longer lifetime than that of the other two distributions.