Design and Analysis of 4-Port MIMO Antenna with Enhanced Isolation for 5G N48/77/78 Band Applications

This article suggests a quad-port orthogonally spaced MIMO antenna for 5G lower-6GHz applications. The simulation findings show that the antenna offers a bandwidth of 700MHz (3.11GHz to 3.81GHz) within the lower band of 5G. By incorporating neutralization lines and circle-shaped decoupling elements in the ground plane, an isolation exceeding 15dB is achieved. The structure uses an FR4 substrate with a dielectric constant <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\epsilon_{r}$</tex> of 4.4 and a loss tangent <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\tan\delta$</tex> of 0.02. The overall dimensions of the antenna are <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$47\times 47\times 1.6\ \text{mm}^{3}$</tex>. The proposed 4-port MIMO antenna features are compact design, improved gain, and outstanding radiation efficiency. Moreover, the recommended MIMO antenna exhibits strong diversity performance, including parameters such as ECC, DG, TARC, and CCL. This antenna is well-suited for communication in the N48/77/78 bands within the 5G sub-6 GHz range.