Distributed flow optimization control for energy-harvesting wireless sensor networks

This paper proposes a distributed flow-based routing technique in energy-harvesting wireless sensor networks (EHWSNs) in order to balance the energy consumptions by sending packets assigned to routers that are sent from sensors to base stations. The objective of the flow optimization problem is to minimize the total load factors of all the nodes and wireless links, which leads to sustainable management of the sensor networks that exploit renewable power from energy harvesting systems. We propose a novel algorithm based on tie-set graph theory where the underlying graph of an EHWSN is divided into a set of independent loops to significantly reduce the topological complexity, which simplifies the flow optimization problem to be solved in a distributed manner. Simulation experiments against the shortest-path and multi-path algorithms demonstrate that optimized packet flows by the proposed method realize the sustainable EHWSNs and maintain the useful life of storage devices with modest increase in total energy consumption by routings.