Threshold voltage self-compensation technology (TVSC) has been widely used in RF energy harvester. In this paper, the influence of the size of rectifying transistors, the stages and compensation orders of the rectifier, and the impedance matching network on the performance of RF energy harvester has been studied. A dual band RF energy harvester with hybrid threshold voltage self-compensation (HTVSC) is proposed in this paper in 65-nm CMOS process according to the distribution characteristic of the ambient RF energy. By combining TVSC and the technology of weak forward bias between the source and body of the rectifying transistor, the threshold voltage of MOSFET can be dramatically decreased. The performance of the RF energy harvester has been improved using this new technology. The simulation results show that the proposed dual band RF energy harvester can acquire energy at the band of 900[Formula: see text]MHz and 2.4[Formula: see text]GHz. At 900[Formula: see text]MHz-band (825–960[Formula: see text]MHz), with 1[Formula: see text]M[Formula: see text] load resistor, the output voltage of the energy harvester can be over 1.0[Formula: see text]V with a minimum [Formula: see text]18[Formula: see text]dBm RF input power and a maximum 13.8% power conversion efficiency (PCE). At 2.4[Formula: see text]GHz-band (2.4–2.485[Formula: see text]GHz), the minimum input power can be as low as [Formula: see text]19[Formula: see text]dBm with a maximum efficiency of 16.8%.
A Design of Ambient RF Energy Harvester with Sensitivity of −21 dBm and Power Efficiency of a 39.3% Using Internal Threshold Voltage Compensation
