title: Three-Phase Time-Multiplexed Planar Power Transmission to Distributed Implants.
abstract: A platform has been presented for wireless powering of receivers (Rx's) that are arbitrarily distributed over a large area. A potential application could be powering of small Rx implants, distributed over large areas of the brain. The transmitter (Tx) consists of three overlapping layers of hexagonal planar spiral coils (hex-PSC) that are horizontally shifted to provide the strongest and most homogeneous electromagnetic flux coverage. The three-layer hex-PSC array is driven by a three-phase time-division-multiplexed power Tx that takes the advantage of the carrier phase shift, coil geometries, and Rx time constant to homogeneously power the arbitrarily distributed Rx's regardless of their misalignments. The functionality of the proposed three-phase power transmission concept has been verified in a detailed scaled-up high-frequency structure simulator Advanced Design System simulation model and measurement setup, and compared with a conventional Tx. The new Tx delivers 5.4 mW to each Rx and achieves, on average, 5.8% power transfer efficiency to the Rx at the worst case 90° angular misalignment, compared with 1.4% by the conventional Tx.
authors.affiliation: GT-Bionics Laboratory, School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30308 USA.
authors.forename: Byunghun
authors.initials: B
authors.lastname: Lee
authors.affiliation: University of California at San Diego, La Jolla, CA 92093 USA.
authors.forename: Dukju
authors.initials: D
authors.lastname: Ahn
authors.affiliation: GT-Bionics Laboratory, School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30308 USA.
authors.forename: Maysam
authors.initials: M
authors.lastname: Ghovanloo
keywords: Distributed neural interface; implantable medical devices; planar spiral coils; three-phase excitation; wireless power transmission (WPT)