Wideband Reconfigurable Transmitarray Antenna Using Tightly Coupling Effect With Wide-Angle Beam Scanning Capability

A wideband reconfigurable transmitarray antenna (RTA) with high aperture efficiency and wide-angle scanning capability is proposed. The RTA design utilizes the tightly coupling effect to take advantage of the mutual coupling between elements, resulting in a wide frequency band. The RTA element employs a transmitter-receiver structure, with each element integrating two p-i-n diodes for 1-bit phase shift via current reversal mechanism. A prototype with 16 x 16 elements is designed, fabricated, and measured. For the measured aperture efficiency above 10.0%, the fractional bandwidth is 49.3% (13.0 GHz to 21.5 GHz), showing excellent wideband performance. At 14.2 GHz and 20.0 GHz, the measured gain is 19.5 dBi and 21.0 dBi, respectively, with corresponding aperture efficiency of 24.5% and 17.5%. 2-D scanned beams up to +/- 60 degrees at two frequencies are obtained, demonstrating a robust beam scanning capability.