A Low-Profile Folded Transmitarray for Single-Shot Random Transmit-Receive Sensing

A low-profile folded transmitarray for dual-random-field sensing is presented. The system relies on a randomly arranged folded array and a single feed source to generate random transmit-receive fields by switching the feed polarization. The folded design with a transmitarray surface (TAS) and a polarization-conversion reflective surface (PCRS) operating over a 34% bandwidth reduces the overall height while maintaining desired sensing functionality. The system has an aperture size of
$\mathbf{12}\lambda\times \mathbf{12}\lambda\times \mathbf{2}\lambda$
with a low height-to-diameter ratio (H/D) of 0.16. The random transmit-receive fields generated by the system allow for more independent measurements and enhanced sensing capabilities and accuracy, which is validated by the sensing results. The proposed compact transceiver has the potential of high-resolution real-time sensing applications.