Energy-Efficient Location-Independent k-connected Scheme in Wireless Sensor Networks*

The reliability of communication can be enhanced by increasing the network connectivity. Topology control and node sleep scheduling are used to reduce the energy consumption. This paper considers the problem of maintaining k-connectivity of WSN at minimum energy level while keeping only a subset of sensor nodes active to save energy. In our proposed scheme, each node is assumed to have multiple power levels and neighbor proximity not exact location information is adopted. Firstly the network partition is attained by power based clustering, and next nodes are divided into equivalent classes according to the role of data forwarding to different adjacent clusters. Then Node Scheduling and Power Adjustment (NSPA) algorithm selects a subset of nodes with different power levels to construct the local minimum energy graph while maintaining network connectivity. If the number of intra-cluster nodes which have adjacent clusters exceeds a certain threshold, k-NSPA is employed. Finally, a k-connected topology can be obtained. The simulation shows that our scheme can obtain the redundant nodes while maintaining network k-connected and it is more energy efficient compared with previous work.