Compact broadband multi-input multi-output antenna covering 3300 to 6000 MHz band for 5G mobile terminal applications

In this letter, a compact multi-input multi-output antenna operating at 3300 to 6000 MHz band is presented for 5G mobile terminals. The antenna includes four vertically placed blocks. Each block consists of two driven monopole elements and one parasitic ground branch. The parasitic branch is shared by both elements. It not only serves as radiator, but also is helpful to improve the port isolation in the lower band. By merging the multiple resonances provided by the driven monopole and the parasitic branch, wideband performance is achieved with a small block size of 28 × 4.2 mm². A prototype is fabricated and measured. The measured −6 dB bandwidth covers 3340 to 6360 MHz band, with port isolation higher than 10 dB. The radiation efficiency of all the ports is higher than 45% across the band.