A Wireless Power and Data Transfer Receiver Achieving 75.4% Effective Power Conversion Efficiency and Supporting 0.1% Modulation Depth for ASK Demodulation

This article presents a 13.56-MHz wireless power and data transfer receiver for implantable biomedical devices. To avoid the efficiency reduction of energy harvesting caused by the large amplitude modulation (AM) modulation depth (MD), and maintain low-power consumption for data receiving, an envelope-detector-based receiver with shifted limiters is designed for signal demodulation. The detectable MD is as low as 0.1%. Moreover, a dynamic impedance matching controller is proposed to adjust the input impedance of the rectifier automatically and thus optimize the power conversion efficiency (PCE). By using these techniques, when keeping the bit error rate (BER) of the proposed receiver to 10^-3 for 100-kb/s data rate in the wireless amplitude shift keying (ASK) data receiver, the effective PCE of the corresponding wireless power receiver can be up to 75.4%.