Efficient Through-Waveguide Wireless Power Transfer for Body Area Networks

This paper focuses on a solution for wireless powering of sensor nodes embedded in an artificial "skin", used to provide a sense of touch to persons using prosthetic limbs. The artificial "skin", that consists of an inner dielectric layer with top and bottom soft metallization, acts as a waveguide, providing means to efficiently guide electromagnetic power to sensor nodes. The proposed solution allows removal of wired connections between soft metallization layers and sensor nodes,that are identified as the primary source of failure. Depending on node distances and propagation conditions, measurements indicate that the available power at the receiving node ranges from 46.8% to 66.1% of the transmitted power. Lower efficiency, compared to wired powering, is thus traded for higher reliability and reduced production cost.