Millimeter-Wave Dual-polarized Active Phased Array Antenna for 5G Applications

This paper presents a millimeter-wave dual-polarized (DP) phased-array antenna in which a $2 \times 4$ stacked-patch array antenna is surface mounted on a feeding structure. The modified stacked-patch antenna is presented. The stacked-patch antenna is prototyped and measured. Measurement results of the radiation pattern show that the array antenna is capable of scanning ±40° in azimuth. Measurement results also show that the active antenna can operate in the 24.5-27.5 GHz band and a good cross-polarization level in both horizontal and vertical polarization is observed. Error-vector-magnitude (EVM) measurement results are $\lt 4.07$ % in the whole frequency band. The proposed active antenna can reduce the difficulty of the multi-layer printed circuit board processing and is suitable for 5G millimeter-wave applications.