Energy-Aware Real-Time Scheduling for Energy-Harvesting Sensor Nodes

Wireless sensor networks based on energy-neutral energy-harvesting nodes have been in the focus of researchers for years as they bring significant benefits regarding the efficiency and the cost of the final product. In this paper, we focus on timing and energy aspects of energy-harvesting sensor node operation. A typical wireless sensor network application enables user to adjust refresh rates of certain measurements which are executed on a sensor node. Energy-aware scheduling of measurements, i.e. task scheduling, is crucial for maintaining target refresh rates demanded by the user. In this paper, we devise an off-line and on-line scheduling approach for energy-aware scheduling of tasks on sensor nodes. Moreover, we show why earlier real-time energy-harvesting models are inadequate in these applications. We evaluated our approach on synthetically generated task sets and initial results show that further research in this direction can bring practical benefits in real-world applications.