Dual-band open-loop monopole (2 x 1) printed MIMO antenna for 4G and 5G applications

This paper presents a compact dual-band open-loop monopole MIMO antenna to serve 4G/5G applications. This antenna consists of two printed monopole antennas with very high isolation. Two enhancement techniques are utilized to improve the isolation between ports. Since each technique can provide high isolation of a single band, a combination of lambda/4 slot and T-shape techniques are used to achieve high isolation of -19 dB and -35 dB at 2.4 GHz and 3.5 GHz, respectively. The proposed design has high efficiency, a low envelope correlation coefficient, and an acceptable level of realized gain (2.7 dBi and 2.2 dBi) at low and high bands. This design has been fabricated using low-profile printed circuit technology with a compact patch size of 50 x 25 mm(2) based on an FR-4 substrate. Moreover, the simulation and measurement results are in good agreement.