A Partially Transparent GSM Band Loop RF-Solar Energy Harvester

In this paper, a hybrid energy harvester consisting of a solar panel and a broadband loop rectenna in GSM 900 band is discussed. The RF energy harvester has a end-fire radiation pattern. This rectenna is useful to harvest energy from the cellular base-station at the same elevation plane. Most hybrid energy harvesters have a broadside radiation pattern for RF energy harvesting which have to be kept at an angle for energy harvesting limiting the solar irradiation of solar panel. The maximum gain of the antenna is 2.06 dBi and the maximum RF to DC efficiency of conversion of rectifier is 57.98 % at 0 dBm input power. The power management unit, consisting of rectifier and buck converter harvests 0.786 V voltage from the rectenna.