A bridgeless rectification circuit for Wi-Fi energy harvesting system

This research proposes a bridgeless rectification circuit for impedance matching and voltage boosting of a Wi-Fi energy harvesting system. The impedance matching is achieved by an LCL T-network in parallel with an inductive branch, and such an arrangement can boost the voltage by combined effect of T-network and bipolarity charging of the output capacitor. The return loss equation and an estimated value of matching circuit parameters are obtained analytically. There are six different modes for the voltage boosting process at two different input cycles. The power converting process is modeled, analyzed, and relevant equations are derived. For the simulation study, the input port of the proposed circuit is designed using a co-planar waveguide arrangement with the input impedance of 52.5Ω. High power efficiency and low return loss at 2.45 GHz are presented by proper circuit analysis and design. Practical measurement results based on an AC power source with an output impedance of 50Ω also verified that the proposed circuit could function as an impedance matching and voltage boosting converter circuit. With the aid of two additional low-voltage boost modules connected at the output of the proposed circuit as loads. It has demonstrated that the output voltage of the final energy buffering supercapacitor can be approximately maintained around 3V for about an hour when the input power of the AC source is set at -30dBm (1uW).