A high-isolation dual-band MIMO antenna for 5G and WLAN applications

This paper presents a compact dual-band Multiple-Input Multiple-Output (MIMO) antenna system with high isolation for mobile terminal applications. The proposed antenna consists of two symmetric folded monopole elements. By etching a U-shaped slot on the radiator, dual-band operation covering LTE (0.8GHz) and WLAN (2.45GHz) bands is achieved. To address the issue of mutual coupling, a T-shaped Defected Ground Structure (DGS) is introduced on the common ground plane. Simulation results demonstrate that the proposed design achieves an ultra-high isolation of greater than 45dB at the WLAN band, with a return loss better than 28dB. The envelope correlation coefficient (ECC) is calculated to be less than 0.005, verifying the system's diversity performance.