A Wideband Reconfigurable Transmitarray Element

Transmitarrays have been shown to be viable architectures for achieving high-directivity reconfigurable apertures. Two reconfigurable transmitarray elements, using single and stacked patches, based on proximity-coupled feeding and two balanced reconfigurable bridged-T phase shifters are presented. Both designs achieve over 400 of phase range and achieve average insertion losses of 3.6 dB. Compared to existing proposed transmitarray elements, the stacked-patch element has a much smaller physical profile, with a lens thickness of only 0.17 λ in free-space, while achieving a large bandwidth of 500 MHz at 5 GHz (10%). Other considerations such as the mutual coupling and beam squint of an array using the stacked-patch element are also discussed.