Reflection Investigation of Modified Greinacher Charge Pump Using Frequency Doubler for an Elegant Full-Duplex WPT System

The power reflection from a 90° hybrid coupler based modified Greinacher (MG) charge pump is investigated by using a frequency doubler, which provides a potential for an elegant full-duplex wireless power transfer (WPT) system. The hybrid coupler is employed as an equal power divider to evenly distribute the RF signal captured by the receiving (RX) antenna for the successive cascaded charge pump, and couple the power reflection from the charge pump's mismatch simultaneously. The frequency doubler absorbs the portion reflection and converts it to second-harmonic frequency., which could drive another transmitting (TX) antenna to enable the second-harmonic feedbacks. The measurement result shows that the second-harmonic generation of-27 dBm is ensured with input power of 4 dBm., which is sufficient for the link budget to realize simultaneous wireless power and information transfer.