Midfield Wireless Power Transfer for Bioelectronics

Midfield wireless powering enables electronics to be designed at the millimeter-scale and operated at nearly any location in the body. Theoretical studies show a wireless power transfer paradigm with a maximum bound orders of magnitude higher than conventional near-field inductive coupling. Furthermore, higher frequency of operation for midfield coupling lends itself to miniaturization of the implant. Midfield powering experiments using an external patterned metal structure and a millimeter sized coil show significant power delivery within safe levels of tissue heating in the chest and the head of a porcine model, and will enable implantable bioelectronics to reach new levels of functionality and one day to become as ubiquitous as over-the-counter pharmaceuticals.