Harmonic-Recycling Rectifier for High-Efficiency Far-Field Wireless Power Transfer

A new harmonic-recycling (HR) rectifier is proposed. Different from conventional rectifiers using harmonic suppression, the proposed rectifier channels the fundamental component generated by the diode to another rectifying element optimized for low-power range, which enables more efficient RF-DC conversion. By implementing a HR unit, additional dc power can be collected with 18% and 11% enhancement in dc output voltage and RF-DC conversion efficiency, respectively. This provides an alternative and more effective method to extract dc power from the incident RF for wireless power transfer application.