Flexible and Semi-Transparent Antenna for ISM Band Fabricated by Direct Laser Writing

In this paper, a flexible and semi-transparent antenna is proposed having impedance bandwidth of 110 MHz (from 2.45 GHz to 2.56 GHz) of ISM band which covers the most popular (2.4 GHz) for Wi-Fi application all over the world. A simple dipole shape rectangular ring antenna with two extended edge on the opposite sides was prepared by laser direct writing on an Au sputtered PET film. The center part of the antenna was kept empty and transparent intentionally to incorporate with either a planar capacitor for microwave wireless charging or to integrate this antenna with a solar cell in future. The compact, miniature and flexibility of the antenna are suitable for easy integration in any smart devices or clothing for wireless charging to implement self-powered sensors. The performance of the patch antenna is evaluated using return loss (S11) parameter analysis. A measured reflection coefficient and simulated current distribution along with radiation pattern demonstrate that the fabricated antenna is suitable for Wi-Fi application.