A compact and efficiently designed two-port MIMO antenna for N78/48 5G applications.

A tightly packed irregular polygon with a distinctive protruding strip, specifically tailored for the N78/48 application, enhances a highly compact and effectively designed two-port MIMO (multiple-input, multiple-output) antenna. Its dimensions measure 20x31.5 × 1.6 mm3, with ε being 4.4 of FR-4 substrate, and it impressively delivers an extensive impedance bandwidth (S < -10 dB) spanning the 3.25-3.85 GHz range. The design incorporates a MIMO antenna with closely spaced elements, merely 1.5 mm (0.012 λ) apart. The microstrip inserts a feeding line with a partially truncated ground, a grounded stub, and a side stubs embedded in the ground plane, which improve isolation. Positioning T shaped decoupling elements between radiators helps the antenna's bandwidth enhance and improves isolation (S) across the band. Extensive validation of the antenna's performance has been carried out through comprehensive s-parameter analysis, closely mirroring the results obtained through measurements. Despite its compact form, this antenna efficiently minimizes coupling, achieving S levels exceeding -19.25 dB throughout the band. Notably, the antenna attains an impressive peak gain of 3.3 dBi and exhibits a radiation efficiency of 92%. A total affective reflection coefficient (TARC) that starts at-10 dB, a MEG of 0.481 dB, and a channel capacity loss (CCL) of 0.3016 bits/s/Hz are some of the things that make up its MIMO diversity performance. The envelope correlation coefficient (ECC) is 0.0089. It's particularly suitable for 5G-NR sub-6GHz requirements, offering an efficient and compact solution.