Co-Design of Dual-Purpose Heatsink Antenna for Multi-Source Ambient Energy Harvesting

IoT infrastructure involves billions of devices that must be self-sustainable. Using ambient energy sources to power IoT devices is a promising solution. Ambient RF and thermal energy (diurnal temperature fluctuations) harvesters have great potential since both are available continuously. Smart integration is required for these two harvesters to create synergy and collect more energy. Here, a dual-purpose triple-band heatsink antenna for multi-source ambient energy harvesting is presented. Heatsink antenna serves as a receiving antenna for the RF energy harvester and serves as a heatsink for the thermal energy harvester (TEH). Co-optimization of the heatsink antenna is performed in Ansys HFSS and Ansys Fluent simultaneously. Heatsink antenna operates at GSM900, GSM1800, 3G bands with measured gains of 3.8dB, 4dB, 5.3dB respectively. Antenna gain is doubled (~3dB) and the TEH performance is tripled (200%) when the heatsink fins are integrated, emphasizing the benefit of the co-design and smart integration via heatsink antenna.