An Energy-Efficient k-connected Scheme for Wireless Sensor Networks

It has been shown that topology control and node sleep scheduling are two effective ways to save power consumption for wireless sensor networks. Moreover, the reliability of communication can be enhanced by increasing network connectivity. In this paper, we study the problem of maintaining k-connectivity of wireless sensor network (WSN) with minimum power levels by keeping only a subset of sensor nodes active to save energy. The main difference from the existing methods is that the proposed scheme only needs the neighbor proximity information, instead of accurate location information. In particular, our scheme is composed of three steps. At First, all nodes in the network form into several clusters, and nodes in each cluster are further divided into equivalent classes based on the next-hop clusters they forward to. Secondly, Node Scheduling and Power Adjustment (NSPA) algorithm selects a subset of nodes to construct a local minimum power graph while maintaining network connected. Finally, within each cluster, if the number of nodes with adjacent clusters exceeds a certain threshold, k-NSPA algorithm is employed to build a k-connected topology. The simulations demonstrate that our schemes are more energy efficient than the previous schemes while keeping the network k-connected.