Body-Channel Wireless Power Transfer Employing Transmitter-Side Received Power Monitoring and Maximum Point Tracking

This paper proposes a power-boosted wireless energy transfer system for wearable devices through human body channels (BC-WPT). The BC-WPT system enables monitoring the received power at the transmitter side and tracking the maximum power point by a tunable LC network. The proposed system has three advantages: First, the system uses the voltage across the insertion resistor between the transmitter and the body electrode to estimate the received power, and the soundness is verified by theoretical analysis; Second, a maximum power point tracking (MPPT) system based on LC resonance is also designed at the transmitter side to maximize the received power under dynamic variations; Finally, the technology does not introduce any extra overhead for miniaturized and low-power sensor nodes, and realizes power boosting. The simulation results show a 17 dB improvement compared to the uncompensated case, and a worst-case improvement of 1.2× than the traditional method of maximizing transmitter power.