An investigation of ambient radio frequency as a candidate for energy harvesting source

In this paper, a feasibility study of the ambient radio frequency (RF) as an energy source to be harvested and converted into electrical energy is presented. This study is to investigate the ability to harvest the ambient RF power density produced by the GSM telecommunication tower for very low power device usage. To capture the RF signal, a normal mode helical rectenna is designed and fabricated. The reason of choosing the normal mode helical antenna in this study is to solve the major problem of a microstrip patch antenna array where the overall size is very large. Experimental results showed that with -10dBm input power, a voltage of 0.3V is generated at the distance 2.5 meters. Hence, this proved that the ambient RF energy can be a suitable candidate as an energy harvesting source.