Flexible Broadband Compact Antenna Using Hydrogel Material for Noninvasive Medical Diagnostic Systems

A flexible broadband compact antenna is presented in this paper. To make the antenna compact and flexible, a high-permittivity polyvinyl alcohol organohydrogel is prepared and used. A magnetic coupling feeding method is used to obtain a broadband design, along with lossy material and head loading. The measured impedance bandwidth is larger than 140%, which is useful for imaging and electromagnetic diagnostic systems.