A Low-profile Wideband Single-Layer Antenna Array for 28-GHz Applications

A novel low-profile printed $4\times 4$ linearly polarized (LP) antenna array is proposed for 28-GHz fifth generation (5G) communication applications. The antenna array adopts a modified magneto-electric (ME) dipole antenna as the antenna element whose magnetic dipole is modified to be C-shaped cavities which reduces the thickness to only 0.787mm. The proposed antenna element is fed through a parallel coplanar waveguide (CPW) feeding network. The antenna elements and the feeding network share the same substrate, making the antenna array single-layered. The antenna array has a bandwidth of 35.7% ($\text{SWR} < 2$) from 21.5 to 32 GHz, which covers the potential 5G frequency bands at 28-GHz millimeter-wave range. Good unidirectional radiation characteristics are also achieved.