Electromagnetic Radiation to Head from Head Implantable Coil Powered via Magnetic Coupling Resonance Wireless Energy Transmission
1 Province-Ministry Joint Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability, Hebei University of Technology, Tianjin 300130
2 Research Department of Frontiers,Institute of Electrical Engineering Chinese Academy of Science, Beijing100190
Abstract：Magnetic coupling resonance wireless energy transmission (Wireless electricity, Witricity) is a new technology that was put forward by MIT in 2007. Witricity achieves middle distance power wireless transmission through magnetic coupling resonance. It has good application prospects in the field of implantable devices because of energy directional transmission and not affected by middle obstacles. In this work a new kind of small size Witricity system suitable for implantable devices was designed. The specific absorption rate (SAR) and electromagnetic field intensity are computed by FDTD through building 3D numerical model of head and implantable coil model with MIMICS and HFSS. Results showed that when transmitting energy to head implantable devices via Witricity, the average 10 g of SAR of head was 9.2627×10-6W/kg, and the mean square root of electromagnetic field intensity were 4.64V/m and 0.057A/m, all of which were below international limit value formulated by ICNIRP.
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