Accurate Analytical Model for Hybrid Ambient Thermal and RF Energy Harvester

An accurate analytical model for the efficiency prediction of a hybrid ambient thermal and RF energy harvester is proposed in this paper. The DC power provided by the Thermoelectric Generator (TEG) is directly influencing the operation of the RF rectification. The proposed analytical model can provide an accurately predicted efficiency performance within a low-power range (< -30 dBm), thanks to a precise separation of each harmonic and DC component generated by diode. This has been verified by comparing with results obtained by both ADS simulation and experiments. Moreover, such a hybrid ambient thermal and RF energy harvester shows an advantage over its hybrid mechanical and RF energy harvesting counterpart in terms of rectified DC output power in the low-power range of interest. This is mainly due to the instinct of DC output converted from thermal energy and its huge contribution.