EPICURUS: Energy ProvIsioning for the start-up proCedUre of batteRyless, wake-Up receiver-enabled Sensors

Batteryless, energy-harvesting sensing devices offer considerable advantages for large-scale, long-term applications since they substantially reduce the maintenance efforts of the underlying equipment. However, the stringent energy budget of such devices leads to them often operating intermittently for a short period before running out of energy and needing to recharge the energy buffer for the next operation cycle. This short operation cycle can become too restrictive when employing peripherals with a relatively long and energy-intensive start-up routine. Therefore, energy management subsystems that can assist the start-up of such peripherals by reducing the imposed energy overhead can significantly increase the efficiency of the entire batteryless device. In this work, we propose EPICURUS, an energy management subsystem that aims to keep a wake-up receiver powered during short power losses of a batteryless device and, therefore, reduce the energy impact of the start-up procedure of the receiver on the rest of an intermittently powered sensor node. Our evaluation shows that EPICURUS reduced the median time and energy required for the initialization of the WuR after short power losses by a factor of approximately 72.12 and 72.36%, respectively. As a result of the more efficient utilization of the harvested energy by the sensor node, it could carry out a sample application by about 26.37 percentage points longer than the baseline while operating intermittently.