Dual-Polarized Folded Reflectarray Antenna With Active Components

This study demonstrates a novel dual-polarized folded reflectarray (DP-FRA) integrated with active components. Conventional FRA consists of three parts: the upper single polarizer grid that lets only a single polarized wave transmit while reflecting the orthogonal one; the bottom metasurface that can convert the
$\boldsymbol {x}$
-(
$\boldsymbol {y}$
-) into
$\boldsymbol {y}$
-(
$\boldsymbol {x}$
-) polarized wave, at the same time, compensating the phase due to the path difference from the antenna source and a feeding source. For the proposed DP-FRA, the upper metasurface unit is composed of three metal layers. The top and bottom metal patches are the same, each integrated with two p-i-n diodes, one along the
$\boldsymbol {x}$
- and another along the
$\boldsymbol {y}$
-direction. A metal patch with a crossed slot is developed in the middle for transmission efficiency improvement. A magnetoelectric dipole is designed as the DP feeding source. The final FRA can achieve a maximum gain of 16.4 dBi, 30% aperture efficiency, and work for dual-polarization operation. It provides a good platform for multifunctional integration.