A fully-passive wireless microfabricated neuro-recorder

Abstract

This paper reports a completely passive and wireless MEMS device for potential use in recording neuro-potentials in-vivo. Its operating principle utilizes an implantable circuit or “tag” to backscatter data to an external interrogator that supplies the fundamental carrier. The backscattering circuit relies solely on its nonlinear components, varactor diodes, which mix and backscatter neuro-potentials with the supplied carrier. Performance of the MEMS neuro-recorder was demonstrated using emulated and in-vivo neuro-potentials as low as 500 μVP-P and up to 3 kHz.