A Novel 1-Bit Reconfigurable Transmitarray Antenna Using a C-Shaped Probe-Fed Patch Element With Broadened Bandwidth and Enhanced Efficiency

A 16 ×16 -element reconfigurable transmitarray antenna (RTA) is designed and experimented in this paper. The proposed element consists of a receiving (Rx) structure and a transmitting (Tx) structure. The rectangular patch with C-shaped probe-fed is designed as the Tx structure to obtain the characteristics of broad bandwidth and low loss, where the U-shaped slot patch is designed as the Rx structure to obtain simple structure. Two PIN diodes are symmetrically integrated on the C-shaped feeding line. By turning them ON or OFF simultaneously, the induced current directions are reversed, thus achieving two phase states with 180° phase difference. The low insertion loss of 0.47 dB and the 3-dB transmission bandwidth of 16.0% are achieved by employing the stepped impedance matching technique. A Ku-band 256-element reconfigurable prototype with 512 PIN diodes is designed, fabricated, and measured. The measured peak gain at 12.2 GHz are 22.1 dBi with aperture efficiency of 21.2% and a 3-dB gain bandwidth of 12.3%. The measured results demonstrate the two-dimensional electronic beam scanning capability within ±60° as well. The proposed 1-bit RTA design exhibits good radiation performance, making it a promising candidate for advanced wireless communication applications.