Development of A Second Harmonic Retrodirective Wireless Power Transmission System with Synchronous Frequency Divider

This study aims to develop a second harmonic retrodirective wireless power transmission system. Conventional second harmonic retrodirective has a problem that the output phase of the divider was unstable and phase information was lost. Therefore, we employs a synchronous frequency divider to suppress irregular phase inversion in the phase conjugate circuit. In addition, a compact dual-band circularly polarized antenna with separate transmitter and receiver ports is designed to avoid grating lobes. Experimental results confirmed that the system functioned properly and power transmission was realized when the pilot signal was input directly to the phase conjugate circuit via a coaxial cable.