A Proposed 2.45 GHz RF-Symmetrical DC Energy Harvester for the Power Unit in the Biosensor

Abstract

This paper presents the proposed inductorless RF-Symmetrical DC energy harvester for low power biosensor transceiver. It is designed to benefit from the symmetrical power supply to reduce the low noise amplifier power consumption of the biosensor reception part. Several techniques are used in this work to design a high efficiency RF-DC harvester with minimum number of stages as: the use of the diode-connected CMOS transistor which its bulk is related to its drain to minimize the leakage current and to reduce the threshold voltage for more energy harvesting, and the use of the Greinacher voltage multiplier to decrease the effect of the voltage drop between the drain and the source of the CMOS transistor. The impedance matching circuit between the antenna and the energy converter is designed without inductors to gain more power and space. Conceived under the 0.18[Formula: see text][Formula: see text]m TSMC MOS technology with only four stages, the harvester simulation results show a high efficiency of 56% which the minimal voluntary received power is about 0dBm required by the IEEE 802.15.4 standard. The symmetrical DC output voltage is of 1/[Formula: see text]1V as expected in the specifications. Therewith, its delivered power is equal to 1mW for storage capacity about 20[Formula: see text]nF.