Recent progress and development of radio frequency energy harvesting devices and circuits

Abstract

Harvesting radio frequency (RF) energy from the environment to power electronic devices has gradually become a mature technology. With the continuous research and development of radio frequency energy harvesting (RFEH) system, it has been expected to replace the battery and applied in wireless sensor networks, wearable devices, Internet of Things and environmental monitoring, etc. However, the performance of RFEH system is limited by the low power conversion efficiency (PCE), narrow dynamic range (DR) and low output voltage of circuits, etc. In this paper, the recent progress and development of RFEH devices and circuits are systematically reviewed. In the RFEH system, antenna is used to receive RF energy, which mainly includes multiband antennas, multiport antennas and array antennas. The impedance matching networks, including the lumped parameter and distributed matching networks, are used for matching the impedance between the antenna and rectifier to achieve maximum power transfer. Non-CMOS, Dickson and Cross-coupled-differential-drive rectifiers are used to convert the received RF signal into dc voltage. The power management unit is adopted to achieve adaptive control, the startup of rectifier, and power conversion. In addition, the comparisons and discussion on the structure, process and performance of RFEH devices and circuits are presented to provide valuable guidance for designing and manufacturing high performance RFEH system. Finally, an outlook on RFEH system is presented, which includes improving the PCE, extending the bandwidth and input DR, and developing accurate optimization design methodology.