A Compact Parylene-Coated WLAN Flexible Antenna for Implantable Electronics

This letter presents a compact planar flexible antenna designed for wireless local area network (WLAN) using simple microfabrication techniques that are compatible with existing state-of-the-art flexible electronic devices. The antenna is fully insulated with biocompatible Parylene C film, which shows a cost-effective and highly feasible approach to making flexible antennas for implantable applications. Coating of ultrathin Parylene C film has shown negligible effects on the return loss and the radiation patterns of the antennas. The characteristics of the proposed antenna have also shown negligible change under different bending conditions. The original WLAN antenna working in air was successfully tuned to operate under implanted condition at 2.4 GHz by tuning the length of the radiator. The measured results showed that the tuned implantable antenna is suitable for integration with flexible and implantable electronics.