Dual-band Dual-polarized Dipole Antenna for Gain and Isolation Enhancements

- A +/- 45 degrees linear-polarized cross-dipole with enhanced gain and isolation has been designed as an example for 5G applications in this paper. By adding stepped reflector and combined director, the isolation and radiation performance of the antenna can be improved significantly. According to the experimental results, the bandwidths with reflection coefficient lower than 10 dB in the low frequency band and high frequency band are 9.5% (3.2-3.52 GHz) and 17.5% (3.86-4.6 GHz), respectively. The dual band can cover 3.3-3.6 GHz and 4.4-4.5 GHz for 5G bands proposed by China's IMT propulsion group. Therefore, the proposed antenna can be widely used in wireless detection, transmission and communication. The isolation of low frequency band and high frequency band can reach above 26 dB and above 22 dB. The average gain is approximately 10.2 dBi in the low frequency band, but the other band is around 6.37 dBi. Compared with commonly used base station antennas, the proposed antenna has been dramatically improved in terms of size, bandwidth, and other electro-magnetic properties.