Miniaturization of implantable wireless power receiver

Implantable medical devices will play an important role in modern medicine. To reduce the risk of wire snapping, and replacement and corrosion of embedded batteries, wireless delivery of energy to these devices is desirable. However, current autonomous implants remain large in scale due to the operation at very low frequency and the use of unwieldy size of antennas. This paper will show that the optimal frequency is about 2 orders of magnitude higher than the conventional wisdom; and thereby the power receiving coils can be reduced by more than 100 fold without sacrificing either power efficiency or range. We will show that a mm-sized implant can receive 100´s muW of power under safety constraints. This level of power transfer is sufficient to enable many functionalities into the micro-implants for clinical applications.