V.N. Koteswara Rao Devana, Arashpreet K. Sohi, A. Swetha, Dhana Raj Valluri, Suman Turpati, Z. Zakaria, A.J.A. Al-Gburi
This study delineates the design, simulation, and empirical evaluation of a compact, adaptable four-port multiple-input multiple-output (MIMO) antenna engineered for seamless incorporation into sophisticated portable and wearable 5G sub-6 GHz devices. The suggested MIMO antenna is made on a flexible polyimide substrate and is 46 × 46.5 × 0.6 mm 3 in size. The antenna has four nested-ring radiators that are fed by coplanar waveguides (CPWs). Each one has a fan-type structure that lets it work over a wide range of frequencies from 2.32 to 7.28 GHz (103.33% fractional bandwidth). Its peak gain and efficiency are 4.42 dBi and 82%, respectively. Partial metallic ground planes with an X-shaped decoupler in the middle work well to reduce cross-coupling effects between the radiating elements and improve impedance matching. The MIMO performance under mechanical deformation is evaluated through bending tests along the X- and Y-directions, demonstrating stable operation and adequate diversity performance. Several diversity parameters are examined and determined to meet standard thresholds, thereby validating the robust correlation between simulated and empirical results. These results show that the proposed antenna is good for sub-6 GHz New Radio (NR) mid-band 5G/IoT applications like n79, Wi-Fi 5/6, and Vehicle-to-Everything (V2X).