Low‐Cost and Highly‐Transparent Reflectarray Using On‐Glass Metal Line and ITO Grid Ground

ABSTRACT In this article, a transparent reflectarray (TRA) based on metal line, soda‐lime glass substrate, and grid ground, featuring low cost, high optical transparency (OT), and high efficiency, is investigated. The indium tin oxide (ITO) grid ground deposited on the soda‐lime glass substrate ensures high OT of the antenna while the metal line with a low square resistivity of 0.017 ohm/sq guarantees high efficiency. Two different element topologies are designed to enlarge the phase coverage and decrease the quantization error. The reflectarray element is implemented between 10.7 and 12.7 GHz, with a full phase coverage of 360° and a low reflection loss of 2.3 dB. Furthermore, low‐cost printed‐circuit‐board (PCB) processing techniques and magnetron sputtering deposition technology are used for manufacturing. To confirm the feasibility and effectiveness of the design, a 24 × 24‐element pencil‐beam reflectarray is fabricated and measured to verify the performance. The measured OT of the reflectarray is higher than 80% and the aperture efficiency reaches 42.5% at 11.2 GHz. Hence, the proposed TRA should be a potential candidate for window, vehicular, and display‐integrated wireless communications.