Wake-Up Radios Quality of Service Adjustment by Leveraging RF Energy Harvesting

Wake-up radios (WuRx) are ultra-low power devices designed to continuously listen to the channel for an incoming message and activate the main node when necessary. The ultra-low power consumption of such devices opens the door to their powering only by exploiting Radio-Frequency (RF) energy. This paper presents the integration of an RF harvester in a WuRx and addresses the goal of optimizing WuRx quality of service based on the available harvested energy. Indeed, the harvested energy depends on the RF received power and the WuRx consumed energy must be adapted to the available energy. Therefore, the number of incoming messages processed by the embedded WuRx microcontroller is adjusted based on battery status, optimizing power utilization and ensuring WuRx sustainability. Using both energy modeling and experimental measurements, we show that the RF harvester is capable of maintaining WuRx operation with input power levels as low as -18 dBm.