A Fully Passive Wireless Backscattering Neurorecording Microsystem Embedded in Dispersive Human-Head Phantom Medium

This letter reports a microfabricated fully passive circuit for extracting and transmitting targeted neuropotentials wirelessly via the backscattering effect without any internal power source or harvester. Radiating electromagnetic waves experience attenuation, phase and wavelength alteration, and random scattering effects when propagating through dispersive biological media (i.e., human head), and these effects are augmented at microwave frequencies required for practical miniaturization of the integrated microsystem antenna. The authors examine the fully passive microsystem for wireless recording of emulated neuropotentials as implanted in a phantom mimicking the human head. The wireless measurements of emulated neuropotentials acquired by the microsystem demonstrate its promising capabilities for neurological applications.