Generic Wireless Power Transfer and Data Communication System Based on a Novel Modulation Technique

This paper presents a wireless power and downlink data transfer system for medical implants operating over a single 10 MHz inductive link. The system is based on a Carrier Width Modulation (CWM) scheme for high-speed communication and efficient power delivery using a novel modulator circuit design. Unlike conventional modulation techniques, the data rate of the proposed CWM is not limited by the quality factors of the primary and secondary coils. The functionality of the new modulation method is proven using a hybrid implementation comprising a custom-integrated demodulator circuit and board-level discrete components. The proposed Wireless Power and Data Transfer (WPDT) system is also capable of operating under a wide range of data rates. It allows a maximum data rate of 3.33 Mb/s for a maximum power delivery of 6.1 mW at 1 cm coils separation distance. The system can recover more power, reaching 55 mW at 100 kb/s. Due to the system genericity, an operator can select the best compromise between power and data rates in accordance to application or current need, without reconfiguring the receiver. Another advantage of this modulation technique is the simple implementation and the ultra-low power consumption of the CWM demodulator despite its high-speed demodulation.