An Internet of Things (IoT) network or a Wireless Sensor Network (WSN) consists of sensor devices and one or more sinks. In general, these sensor devices monitor or collect samples of targets, e.g., vehicles, or their surrounding environment; e.g., the temperature of a room. They then upload their collected samples to a sink for further analysis. A critical issue when operating sensor devices is their energy limitation. To this end, researchers have considered charging sensor devices using a variety of sources, include solar, wind, and Radio Frequency (RF). Consequently, sensor devices with energy harvesting capability are able to operate perpetually assuming they do not spend more than their harvested energy. Apart from energy harvesting technologies, researchers have recently exploited the negligible energy cost afforded by backscatter communications. Consequently, it allows sensor devices to use more of their harvested energy to collect samples that otherwise would be used for acti