Miniaturized Triple-Band Highly Transparent Antenna

In this article, a novel on-glass antenna which is transparent, miniaturized, and multiband is presented. First, the antenna achieves more than 80% transparency. This is realized by removing as much as possible the metal pattern, without compromising the operational electric current flow. Second, the antenna is electrically small, $0.13\lambda \times 0.19\lambda $ at 0.95 GHz. This is realized by choosing a proper topology for the remaining metal pattern. Third, the antenna is triple band, covering the ranges 0.88-1.03 GHz, 1.47-2.74 GHz, and 3.32-5.97 GHz. The radiation is omnidirectional in all bands, which is suitable for GSM900/1800, 3G, 4G, 5G (2.55-2.65 GHz), WLAN (2.4/5.2/5.8 GHz), and WiMAX (2.5/5.5 GHz). The maximum gain in the three bands is equal to -0.18, 3.66, and 4.35 dBi with corresponding radiation efficiencies of 66%, 87%, and 88%. A prototype is made by first printing a metallic circuit on a thin FR-4 substrate and then gluing it on a glass substrate. The measurement results are in good agreement with simulations.