Dual-band Dual-polarized Scalable Phased Array Antenna with High Isolation and Polarization Purity for 5G Millimeter Wave Applications

A dual-band dual-polarized stacked patch antenna in package (AiP) operating at 28 and 39 GHz is proposed for 5G millimeter wave scalable phased array applications. With the isolation structure and differential feeding, the isolation between two polarization ports of the antenna element is greater than 50 dB, which is 10 dB higher than that without the isolation structure. Moreover, the cross-polarization isolation is greater than 30 dB. The 10-dB impedance bandwidth of the lower band starts from 27 to 28.4 GHz and the higher band covers the 38 to 39.5 GHz. The antenna has the advantages of simple structure, compact size and stable gain, making it suitable for the phased array antenna. Based on proposed antenna element, a 16-element phased array antenna, consisting of four scalable 2×2 subarrays, is designed. With simulations, it is proved that the antenna shows good beamforming performance in both frequency bands.