Design and Characterization of Wireless Power Links for Brain–Machine Interface Applications

In this paper, the design of an inductive power link (IPL) for wireless power transfer (WPT) in brain-machine interface (BMI) applications is thoroughly studied. The constraints and requirements of BMI applications are analyzed. By theoretical derivations, the relationships between the IPL performances and its electrical parameters are determined. The design guidelines for the IPL physical parameters are then obtained through experimental characterizations. Experimental results show that with proper IPL design, the efficiency can be improved from the previously reported values of 29.9% and 4.3% to 33.1% and 9.2% for BMI WPT distances of 5 and 12.5 mm, respectively.