Modified four-port dual-band (FPDB) scaled rectangular inset-feed MIMO antenna for 5G-millimeter-wave applications including 28.0 GHz/38.0 GHz bands

This research focuses on a Four-Port dual-band (FPDB) MIMO antenna in millimeter-wave applications. The antenna is compact occupying an overall dimension of 12 × 11 mm² printed on Rogers-Dielectric 2.20 utilizing opposite surface for the printing of radiating patch and ground. An elliptical slotted square patch is used to achieve 28.0 GHz resonance and by scaling the antenna patch by a factor of 0.72, the resonance shifts to 38.0 GHz with additional resonance at 28.0 GHz achieved by embedding rectangular-stub. For better matching of impedance, the antenna is inset-fed and the four-port configuration achieves measured operating bandwidth of 26.32–29.76 GHz and 36.82–38.89 GHz. The proposed MIMO antenna includes desirable 2-D radiation patterns in the Elevation and Azimuth plane with a peak gain of 6.77dBi at 28.0 GHz and 9.46dBi at 38.0 GHz. The measured diversity parameters include ECC < 0.0056, DG \(\cong \) $\cong$ 10.0 dB, TARC < − 10.0 dB, CCL < 0.32 b/s/Hz, MEG \(\cong \) $\cong$ − 3.0 dB, and MEG-Ratio of \(\cong \) $\cong$ 0.0 dB. The SAR values also correspond to 0.6825 W/kg at 28.0 GHz and 0.3357 W/Kg at 38.0 GHz suggesting the features of the proposed work are suitable for future millimeter-wave applications.