Dual-Band Orthogonally-Polarized Dual-Beam Reflect-Transmit-Array With a Linearly Polarized Feeder

This communication presents a novel bifunctional metasurface (MS) combining the reflectarray (RA) and transmitarray (TA) with dual-band orthogonally polarized dual-beam characteristics. The proposed reflect-transmit-array (RTA) is capable of reflecting the
$x$
-polarized incidence without changing its polarization state around 10 GHz while transmitting the
$y$
-polarized incidence and converting it into the circularly polarized (CP) waves around 14 GHz. To completely cover the working frequency bands of both modes, an antipodal Vivaldi antenna (AVA) is introduced as the source feed due to its intrinsic ultrawideband characteristics. As a proof of concept demonstration, a prototype consisting of 20
$\times20$
elements is also designed, fabricated, and measured. We observe a good agreement between the measurement and simulation results that shows a peak gain of 26.2 dBi and 27.3 dBic, 1 dB gain bandwidth (BW) of 9.8–11.3 GHz (14.2%) and 12.8–14.2 GHz (10.4%), and peak aperture efficiency (AE) of 48.7% and 35.1% for the reflection and transmission modes, respectively.