An efficient wireless power link for implanted biomedical devices via resonant inductive coupling

This study presents a high efficiency inductive power link aiming for the implanted biomedical devices. Improving the efficiency of the inductive link is critical, since the overall efficiency of a remote powering system is dominated by the inductive link. Therefore, the proposed system utilizes the resonance phenomenon which enables maximum energy transfer between objects which are at resonance. In this study, the resonance is created between 4 spiral coils which are implemented on the internal and external units; each formed by two concentric coils. The system operates with 72% power efficiency at 10-12 MHz band at 10 mm distance which is a reasonable distance for powering implanted devices. Moreover, the characterization of the resonant inductive link with respect to distance and frequency is performed.