This article presents a compact, low profile, four ports multiple-input-multiple-output (MIMO.) antenna operating at the n38 and n41 5G frequency bands. The antenna has a measured -10 dB bandwidth of 2.5-2.9 GHz with isolation less than -11 dB. The designed antenna system employs open slot radiators etched on a single-sided rectangular PCB substrate with a total size of 40 ×100 mm2, including a ground plane. The open slot radiators are symmetrically printed at the four corners of the rectangular substrate. The radiators are excited by 50-Ω strip lines. Rectangular-shaped slits are used as decoupling structures. MIMO parameters such as the envelope correlation coefficient (ECC), channel capacity loss (CCL), and mean effective gain (MEG) are being calculated using the measured results. The ECC is less than 0.1 over the entire operating band despite the antenna's small size. The proposed antenna shows good performance in two sub-6-GHz frequency bands for 5G NR applications: n38 (2570 to 2620 MHz) and n41 (2496 MHz-2690 MHz).
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