Powering Wireless Sensor Networks with Solar Generated RF

Powering Wireless sensor networks (WSN) is one of the most researched topics in the wireless field. Due to the density of such networks, conventional power sourcing using wires is not feasible. Furthermore, a sensor node (SN) in a WSN consumes small amounts of energy. Therefore, the SN can be charged wirelessly using a radio frequency (RF) power transmitter. This paper presents a solar-powered simultaneous wireless information and power transfer (SWIPT) transmitter design with dynamic power allocation (DPA). Moreover, a receiver design with separate energy harvesting (EH) and information decoding (ID) circuitries is adopted. DPA carries the communication signal on low-power subcarriers around the carrier frequency, while the energy signal is carried on a high-power continuous wave (CW) centered at the carrier frequency. DPA reduces the interference to external networks by limiting the high power signal to a few subcarriers. Furthermore, the split receiver design increases the harvested power at the EH circuit reservoir.