Lifetime-aware data collection in Wireless Sensor Networks

In WSNs (Wireless Sensor Networks), sensor nodes are typically battery powered. As a result, network lifetime becomes a major optimization objective in the design of a WSN. We investigate the problem of lifetime-aware data collection in a WSN with only one base station. We propose an efficient distributed algorithm for constructing a routing DAG (Directed Acyclic Graph), namely, R-DAG, for data collection. Our algorithm makes use of a shortest path DAG and adds sibling edges to balance the loads of the base station's children, prolonging the network lifetime. The simulation results show that the R-DAG significantly outperforms the shortest path DAG. For the 60 instances of WSNs generated by using Cooja simulator, the average improvement and the maximum improvement in network lifetime achieved by the R-DAG over the shortest path DAG are 42% and 99.5%, respectively.