A Sub-6 GHz 5G Dual-Band MIMO Antenna with High Isolation

This article presents a quad-port MIMO antenna with dual-band resonance for sub-6 GHz 5G applications, a dual-band CPW-fed single-element antenna constructed into a quad-port MIMO structure. The planar rectangular patch antenna with coplanar waveguide (CPW) feed is excited to attain dual-band resonance using two arm-like structures on both sides of the planar rectangular patch. The slits on both arms are about 0.5 mm thick. The proposed structure resonates with a fractional impedance bandwidth of 50.8%, which covers 2.2 to 3.7 GHz, and 29.74%, which covers 4.75 to 6.41 GHz. Isolation between the elements shows a value less than -20 dB in all operating frequencies without decoupling structures; the isolation is enhanced by the orientation of antenna elements. The MIMO antenna has a compact size of 50 mm by 50 mm, and isolation between the components is enhanced by keeping the elements apart at 10 mm. Various diversity parameters of the MIMO design are validated through simulation results.