volume | PIER Journals

Abstract

A compact four-port multiple-input multiple-output (MIMO) antenna operating on the N79 band (4.4-5.0 GHz) is designed for use in 5G wireless communication systems. The suggested antenna is synthesized over an FR4 epoxy substrate with a relative permittivity of ε_r = 4.4, and a standard height of 1.2 mm. The overall dimensions of the antenna are 45 × 45 × 1.2 mm³, making it suitable for insertion into miniature 5G-enabled portable devices. A novel defected ground structure (DGS) is proposed, employing the strategic placement of two stubs of unequal lengths within the shared ground plane to effectively mitigate surface-wave propagation and thereby suppress mutual coupling among antenna elements. Thus, the design achieves considerable isolation, with a level below -20 dB across the targeted operational band. The suggested antenna operates at 4.67 GHz with a peak gain of 2.83 dBi and a radiation efficiency of 92%. The performance of the MIMO antenna was comprehensively assessed using standard diversity metrics, achieving an 0.01 envelope correlation coefficient (ECC), a diversity gain (DG) of 9.99 dB, a channel capacity loss (CCL) of 0.36 bits/s/Hz, and a mean effective gain (MEG) consistently below -3 dB. A strong correlation between experimental and simulated findings points towards the robustness of the suggested design. With its compact size, high isolation, and excellent MIMO performance, the antenna demonstrates strong potential for integration into sub-6 GHz 5G MIMO wireless communication systems.

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Dr. Prabhu Kumar Kothavari

Prof. Venkata Rajasekhar Nuthakki