A Dual Band Polarization Reconfigurable Transparent Antenna Design

This paper presents a dual-band polarizationreconfigurable transparent antenna. The antenna is fabricated by etching indium-tin oxide (ITO) transparent conductive film, with a thickness of 0.125 mm, onto a 0.1 mm thick polyester (PET) substrate, achieving an overall light transmittance of 87%. The antenna design comprises two circular monopole patches and a surrounding frame. The circular monopole patches are coupled and fed via T-shaped feedlines. Four diode switches, mounted on the ITO surface using conductive silver paste, enable control over the antenna's polarization. By varying the bias voltage, three polarization states can be realized: linear polarization, left-handed circular polarization, and right-handed circular polarization. The antenna's performance was evaluated through simulation conducted on a vehicular glass substrate. The antenna has size of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$96.7 \times 68.9 ~\text{mm}^{2}$</tex> with a total thickness of 0.225 mm. It exhibits a linear polarization matching bandwidth of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$2.3-6.5 \text{GHz}$</tex> and a circular polarization bandwidth of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$5.4-6.4 \text{GHz}(\mathbf{1 5 \%})$</tex>.