Compact Orthogonal UWB MIMO Antenna with Fractal-Slotted Design for Enhanced Isolation in 5G-NR and X-Band Applications

In this proposal, an advanced integrated multiple-input multiple-output (MIMO) antenna system has been presented for next generation 5G-NR, high speed WLAN and X-band communications. The four radiators having comb-shaped geometry at the top edge are positioned orthogonally with each other. An adequate gap is maintained between the radiating ports of MIMO antenna to lower down the mutual coupling. A small fractal geometry is engineered at the bottom corners of the patch to receive size miniaturization, wide band performance and manufacturing advantage. In similar fashion, thin slots are introduced to excel the isolation. The ultrawide band response (1.6 GHz-11.35 GHz) could be achieved by introducing partial ground plane underneath each radiator. A commercially available Flame Retardant 4 substrate was utilized. The individual ground structures are interconnected using thin conducting strips, which play a dynamic role in system performance by providing high isolation between the MIMO elements. The proposed MIMO system is analyzed and confirmed based on various antenna responses such as diversity gain (DG) (>9 dB), mean effective gain (MEG) (-6 to -8 dB), channel capacity loss (CCL) (< 0.4 bits/s/Hz), and envelop correlation coefficient (ECC) (< 0.002 abs). The received reflection coefficient values from the MIMO antenna are compared with actual values. Both the responses are closely aligned with each other. This research supports SDG 9, SDG 11, and SDG 7 by advancing innovative wireless communication infrastructure, enabling sustainable and resilient smart city connectivity, and indirectly promoting energy-efficient network operations through high-isolation and efficient antenna design.