A Conformal Dual Frequency Wireless Power Transfer System Based on Magneto-Inductive Waveguides

This paper presents a numerical analysis of a conformal dual frequency Wireless Power Transfer system based on magneto-inductive wave phenomenon. By exploiting accurate numerical simulations, we conceived an arrangement consisting of a single actively fed RF transmitter linked through two magneto-inductive waveguides to the corresponding receivers. The selected working frequencies, 13.56 MHz and 40.68 MHz, lie within the ISM available bands, making the system suitable for biomedical applications, as power transmission to implantable devices, and for other consumers devices. Maximum efficiencies of 1.45% and 12.5% are achieved at 13.56 MHz and 40.68 MHz, respectively. Moreover, the proposed system requires a single layer of elements, allowing a more compact and potentially conformal realization of power transmitting devices with respect to traditional WPT systems based on external driving coils. In addition, the absence of cables and connectors linking the transmitting coil with the receivers enables wireless signal propagation even with large and arbitrarily complex separating paths.