Ultrasonic Power and Data Link for Wireless Implantable Applications

Wireless implantable devices revolutionize the field of biomedical engineering as soon as satisfactory power supplies are conceived. This paper presents a novel ultrasound-based method for powering a battery-free electrical implant. Contrary to the commonly used RF and inductive methods, ultrasonic power transmission helps to avoid problems with electromagnetic coupling and offers for use a selection of data frequencies not limited by national regulations. The proof-of-concept data and power link is based on piezoelectric crystals. Measurements carried out in degassed water brought perspective to the feasibility of an ultrasonic link. Efficiencies of 21-35 % at distances between 5 mm and 105 mm were achieved