A 24-GHz Directional Button Antenna for Wireless Power Transfer on Human Arm

A directional button antenna working at 24 GHz of ISM band is proposed for Wireless Power Transfer (WPT) on human arm. It consists of the feed of microstrip line, the monopole antenna loaded dielectrics, and the AMC structure close to the feeding port. The WPT and communication antennas are placed on the real human arm model of a Chinese female, the interactions between arm and antenna are investigated, including the matching, the channel characteristics, the pattern, the specific absorption rate (SAR), and the transmission efficiency.