Capacitive detuning optimization for wireless uplink communication in neural implants

This study presents a wireless energy and data transfer system for neural implants with an emphasis on epilepsy monitoring. A wireless uplink data transmission system is built upon a remote powering system based on magnetic coupling which has been implemented previously. Uplink communication from the implant unit to the external base station is realized by shifting the resonance frequency of the load coil in the implant side. Effect of different detuning capacitances on power transfer efficiency and energy per bit is investigated. The in-vitro measurements of the system exhibits 32% power transfer efficiency while transferring 1 Mbit/s data from 10 mm distance at 8.5 MHz using a detuning capacitance of 120 pF. Furthermore, an optimization based on data rate, energy per bit, and power transfer efficiency has been proposed for the resonance frequency shift keying method.

[1]  Catherine Dehollain,et al.  A Wireless Power Link for Neural Recording Systems , 2012 .

[2]  Swee Hin Teoh,et al.  Cranioplasty after Trephination using a Novel Biodegradable Burr Hole Cover: Technical Case Report , 2006, Neurosurgery.

[3]  Chua-Chin Wang,et al.  Self-Sampled All-MOS ASK Demodulator for Lower ISM Band Applications , 2010, IEEE Transactions on Circuits and Systems II: Express Briefs.

[4]  Igor M. Filanovsky,et al.  CMOS Schmitt trigger design , 1994 .

[5]  Maysam Ghovanloo,et al.  Design and Optimization of a 3-Coil Inductive Link for Efficient Wireless Power Transmission , 2011, IEEE Transactions on Biomedical Circuits and Systems.

[6]  Naveen Verma,et al.  Ultralow-power electronics for biomedical applications. , 2008, Annual review of biomedical engineering.

[7]  S D Lhatoo,et al.  The treatment of epilepsy in developing countries: where do we go from here? , 2001, Bulletin of the World Health Organization.

[8]  M. Soljačić,et al.  Wireless Power Transfer via Strongly Coupled Magnetic Resonances , 2007, Science.

[9]  Oguz Atasoy,et al.  Wireless Energy and Data Transfer for In-Vivo Epileptic Focus Localization , 2013, IEEE Sensors Journal.

[10]  Catherine Dehollain,et al.  An efficient wireless power link for implanted biomedical devices via resonant inductive coupling , 2012, 2012 IEEE Radio and Wireless Symposium.

[11]  C. Schroeder,et al.  Spatial characterization of interictal high frequency oscillations in epileptic neocortex , 2009, Brain : a journal of neurology.