Abstract
In this paper, a frequency reconfigurable multiband multiple-input-multiple-output (MIMO) antenna is developed for 5G communication systems. The presented MIMO antenna element consists of a 50 ohm microstrip line, a rectangular monopole divided into two patches, and a partial ground plane. A split-ring resonator (SRR) is introduced into the upper patch to cover multiple 5G application bands, and an RF PIN diode is embedded between the upper and lower patches to enable the frequency diversity feature. In order to design a MIMO antenna with improved inter-element isolation, four antenna elements are orthogonally located with ground planes connected to each other. The antenna design covers the n41/n46/n48/n79 5G application bands. The prototype MIMO antenna is developed on the FR-4 substrate, and the measured results match with the simulated outcomes. The overall footprint of the prototype antenna is 70 x 70 x 1.6 mm(3).