Quad-port 28/38 GHz Antenna with Isolation Improvement for 5G Wireless Networks

A 28/38 GHz quad-port cross-shaped antenna printed on a 0.203 mm Roger RO4003 substrate is designed and fabricated for 5G networks. The antenna consists of a rectangular patch radiator with three triangle slots to enhance the antenna's impedance matching. The four elements are arranged in a cross-shaped layout to achieve the desired compactness of 29 mm x 24.2 mm x 0.203 mm. A thin parasitic strip is inserted between the second and fourth elements to enhance the port isolation. The designed antenna is simulated by utilizing the CST simulator. The antenna achieved S11 < -10 dB at 28 / 38 GHz, with isolation >= 20 dB. Furthermore, the E- and H-planes within the anechoic chamber are evaluated to validate the MIMO antenna radiation patterns and gain. The MIMO parameters are calculated, simulated, tested, and its outcomes are under the standard level which confirms the MIMO diversity feature. The ECC of the structure is < 0.001, the DG >= 9.95 dB. and the CCL was <= 0.2 bit/s/Hz across the dual working band.