Synergistic multi-source ambient RF and thermal energy harvester for green IoT applications

In a future green Internet of Things (IoT) reality, billions devices the IoT infrastructure should be self-powered. Harvesting ambient energy to power is an attractive solution that can extend battery life or completely replace batteries. Considering global applications IoT, ubiquitous and continuous availability important requirement for sources. Radio frequency (RF) from mobile phone towers thermal diurnal cycle temperature fluctuations are good candidates. this study, we present synergistic multi-source harvester (MSEH) comprising RF (RFEH) (TEH) integrated through dual-function component, heatsink antenna. Both harvesters collect 24 h day not location specific. The TEH, which in shape box, collects using heatsinks on its sidewalls. same optimized also serve as receiving antennas RFEH, GSM900, GSM1800, 3G bands. Due integration, radiation efficiency antenna doubled 40% 80% resulted ∼10% increase conversion RFEH. Similarly, average TEH without 120 μW 240 with heatsinks. Field tests have shown outputs RFEH increased 4 3 times compared independent respectively. A humidity sensor based node has been successfully powered harvesting system. Overall, MSEH 3680 μWh per sufficient obtain sensors data time interval 3.5 s.