A flower-shaped dual-band four port MIMO antenna with novel DGS for 5G mmWave applications

A novel quad-port multiple-input multiple-output (MIMO) antenna with enhanced isolation is proposed by incorporating a specifically designed hybrid defected ground structure (DGS) for dual band 5G mmWave wireless applications. This suggested MIMO antenna system features a distinctive DGS, consisting of a central circular slot combined with four surrounding trapezoidal cut-outs at the base of the ground plane for enhanced isolation and comprises four identical elliptical monopole elements. Initially, a four-element MIMO system is developed to achieve optimal performance. Subsequently, the conFigd hybrid DGS is included in the proposed structure to improve the isolation by effectively analyzing the impact of alterations in the various geometrical parameters of the DGS. The designed MIMO radiator resonates at 26.73/38.29 GHz and operates from 26.39 to 27.04 GHz and from 38.11 to 38.47 GHz, achieving gains of 4.80 dBi and 7.61 dBi at 26.73 GHz and 38.29 GHz, respectively, maintaining a compact size of 21 mm × 21 mm (1.849 λ × 1.849 λ). The designed four-port MIMO radiator demonstrates exceptional performance in terms of various impedance, radiation and diversity metrics. The design and simulation studies are conducted using the CST simulation tool. Finally, the intended antenna has been prototyped and experimentally tested, confirming the correctness of the simulation analysis. The proposed antenna partially operates within 5G NR mmWave n258/n260 bands and is suitable for 5G Fixed Wireless Access (FWA) applications.