A single layered high-gain digital metasurface reflectarray antenna for millimeter wave applications

A high-gain digital metasurface reflectarray antenna for 5G FR-2 band is presented in this letter. The digital metasurface reflector is composed of single-layered phase quantized meta-bit unit cell elements. The metabit consists of a split square integrated with a circular ring. Two discretized phase states are obtained by varying the dimensions of the split square and the circular ring, which mimic the metabit-0 and metabit-1, respectively. A digital metasurface reflectarray having dimensions of 5.3 & lambda;o ${{\boldsymbol{\lambda }}}_{{\boldsymbol{o}}}$ x ${\boldsymbol{\times }}$ 5.3 & lambda;o ${{\boldsymbol{\lambda }}}_{{\boldsymbol{o}}}$ operating in the frequency range of 37-39 GHz is designed, fabricated, and characterized. A linearly polarized antipodal vivaldi antenna spatially feeds the digital metasurface reflectarray. A maximum measured gain of 19.1 dBi is obtained at 38 GHz, with an aperture efficiency of 23%.