Design of an enhanced RF energy harvesting system for wireless sensors

In this paper, a technique is proposed for enhancing energy harvesting devices. The design is capable of charging small power consumption sensors by capturing ambient radio frequency (RF) waves. The technique comprises the use of high-profile monopole antenna array with a reflector in order to maximize the RF energy received by the antenna system. Furthermore, a prototype of the proposed RF energy harvesting system was built, and tested in laboratory. The proposed design is compared with a reference case that uses only a single monopole antenna element at both transmitter and receiver sides. The achieved results show better performance in terms of captured output direct current (DC) voltage in comparison to that captured energy by the reference prototype with a single antenna element. The designed system is useful in many wireless applications and can easily be integrated with other high-gain antenna systems to further maximize the harvested energy.