Miniaturized Wideband MIMO Antenna based on Hybrid Isolation Technique

A compact wideband two-port multi-input-multi-output (MIMO) antenna for 5G sub-6 communication is proposed in this research. The MIMO antenna consists of a coplanar waveguide and a Moore fractal based on the second iteration, comprising two T-stub shapes designed to achieve the desired frequency band and enhance the capacitive coupling effect. To improve the return loss and isolation between the two elements, closed rectangular ring metamaterials and a neutralization line are incorporated, resonating across 2.7–5.3 GHz (2.55 GHz) with high isolation below -20 dB for the entire frequency band. The proposed antenna has dimensions of 31×50 𝒎𝒎𝟐 with thicknessof 1.6mm. The suggested MIMO design is fabricated using low-cost FR4, and its S-parameters, gain, and radiation patterns are measured. Simulation and fabrication measurements demonstrate an envelope correlation coefficient below 0.005, indicating excellent spatial diversity performance. Additionally, the capacity loss is found to be less than 0.3 b/s/Hz, highlighting the antenna's efficiency in maximizing data transmission rates for 5G sub-6 communication.