A Wide-Range Highly Power Efficient RF-to-DC Rectifier for RF Energy Harvesting Systems

In this paper, a wide input range, 4-stage threshold voltage compensated RF-DC power converter is introduced. A novel threshold voltage compensation scheme is proposed that can be applied to a rectifier chain with a relatively low number of stages. This proposed structure is shown to provide a high power conversion efficiency (PCE) over a wide input power range that increases the coverage area of wireless powering. Designed and simulated in IBM 130-nm CMOS technology, the proposed 915-MHz rectifier exhibits a PCE of above 20% over the 20-dB input power range while driving a load resistor. For the same load, utilizing a minimal number of compensated rectifier stages, the proposed circuit exhibits a record maximum PCE of 52% at -10 dBm for single-ended Dickson-based CMOS rectifiers. The proposed circuit demonstrates a -22.3 dBm sensitivity for 1 V output across a 1-MΩ resistive load.