A Layer-Substitutable Dual-Circularly-Polarized Reflect-Array at X-band

Abstract

We present an X-band layer-substitutable dual-circularly-polarized (dual-CP) reflect-array (RA) with two replaceable functional layers. A circular polarization selective surface (CPSS) is employed as the top functional layer to realize handedness discrimination of CP waves, which reflects one handedness CP wave and transmits the other orthogonal one. A half-wave plate layer is utilized as the bottom functional layer to reflect the CP wave transmitted from the top functional layer. Berry phase compensation is adopted to achieve the dual-CP performance with the two functional layers, respectively. This RA has a diameter of 230 mm, consisting of 186 CPSS cells and 238 half-wave plate cells. A peak gain over 23.5 dBic can be achieved, along with a joint axial ratio < 2 dB with gain variation < 2 dB bandwidth of 19%. In light of the layer-replaceable merit and wideband performance, this proposed dual-CP RA can be useful for Earth observation, satellite communications, and so on.