Ultracompact Dual-Polarized Cross-Dipole Antenna for a 5G Base Station Array With a Low Wind Load

Very high wind loads represent one of the major problems for ultralarge-scale 5G base station arrays in the sub-6 GHz band, where dozens or even hundreds of antennas are used. An ultracompact dual-polarized cross-dipole antenna with an extremely small overall projected area is presented. The projected area is reduced by employing miniaturized cross dipoles and replacing the traditional ground plane with a defected ground structure (DGS) and metal mesh reflector. The DGS is utilized for size reduction and isolation enhancement. Therefore, an array with a low wind load is formed using antennas with an extremely small projected area, and each antenna in the array can be independently packaged using a streamlined radome that is conducive to airflow. The antenna prototype is designed, fabricated, and measured for the sub-1 GHz band. The results show that the impedance bandwidth is 680-970 MHz, the polarization isolation is higher than 20 dB, and the gain is approximately 6.5 dBi. Furthermore, the results verify that the proposed ultracompact antenna with excellent radiation performance is highly suitable for an ultralarge-scale 5G base station array with a low wind load.