Simultaneous Wireless Power and Data Transfer to Biomedical Implants via Series-Resonant Capacitive Links

This paper investigates the performance of series-resonant capacitive links for simultaneous wireless power and data transfer to biomedical implants. A novel method leveraging balanced signals and geometrical symmetry in capacitive plates arrangement is proposed to reduce the interference between the two separate power and data links by ~ 22 dB, enabling reliable simultaneous operation. The proposed technique is validated through simulations and ex vivo measurements with a 2.5 mm-thick beef tissue slice, where the data link operates at 12.5 MHz and the power link at 8.3 MHz. The proposed link configuration achieves a measured maximum power transfer efficiency (PTE) of 58.6% and power delivered to the load (PDL) of 83.6 mW for the power link. The data link achieves a high data rate of 25 Mbps with a bit error rate (BER) of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$&lt; 10^{-3}$</tex>.