Simultaneous Wireless Data and Power Transfer System Utilizing Frequency Characteristics of Magnetic Resonance with Output Power Fluctuation Suppressed

Abstract

A circuit of simultaneous data and power transfer systems exploiting frequency shift keying (FSK) in the magnetic resonance wireless power transfer (MR-WPT) circuit is proposed. The proposed circuit attains FSK based on the frequency characteristics of the MR-WPT circuits known as frequency splitting phenomenon and contains a frequency control circuit using a phase-locked loop to enhance robustness against a fluctuation of a load and a coupling coefficient between transfer coils. The proposed circuit is implemented on the designed printed circuit board with off-the-shelf integrated circuits. In addition, an FSK demodulator using an FPGA is also presented and implemented. Experiments reveal the feature of output power insensitive to the space between coils. The proposed circuit achieved transmitting data at a bit rate of 57.6 kbps and delivering 0.60-W power with 32.4% efficiency at the coupling coefficient between transfer coils of 0.36 for the 1.01-Ω ohmic load.