Dual-Polarization Wideband Sub-6 GHz Suspended Patch Antenna for 5G Base Station

This letter presents a simple, compact, low-cost, low-profile, dual-polarization, suspended patch antenna design to operate in 3.3-3.8 GHz band for 5G base stations. The proposed antenna comprises a main radiating patch, a secondary parasitic patch, modified L-probe feeds, and a vertical metal wall. The main patch is capacitively driven by two feeds for dual (+/- 45 degrees slant) polarization. The vertical metal wall is used to increase the port isolation. The parasitic patch also helps further improvement of input impedance matching (|S-11|, |S-22|) and port isolation (|S-21|). The prototyped antenna has |S-11|, |S-22| < -10 dB and |S-11|, |S-22| < -15 dB impedance bandwidth of 45% and 36%, respectively. Port isolation is |S-21| < -30 dB in the desired operating band. Stable and symmetric radiation patterns with half-power beamwidths of 56 degrees-65 degrees are obtained in E-/-H-planes. The gain of the antenna is 8.95 +/- 0.25 dBi. Numerical calculations and experimental results are reported and discussed.