Dual-polarized single-layer reflectarray as passive reflecting surface for 5G applications

A single layer reflectarray configuration is investigated to achieve a dual-polarization operation mode, at millimetre-wave frequencies. The reflectarray cell is proposed as a viable solution for future implementations of passive reflecting surfaces for 5G applications. The proposed configuration offers independent phase tuning in each polarization, a very thin structure ($\cong 0.0237 \lambda$ at $f=28 \mathrm{GHz}$), and small cell sizes ($\cong 0.4 \lambda$ at $f=28 \mathrm{GHz}$), thus preserving the ability to focus the main beam at large scan angles. A dual-polarized reflectarray prototype is preliminarily designed and numerically tested, demonstrating the ability of the unit cell to provide independent radiation characteristics for each polarization.