Planar dual-band 27/39 GHz millimeter-wave MIMO antenna for 5G applications

This research work presents another design of a multi-input multi-output (MIMO) antenna with dual wide operating bands at the millimeter-wave (MMW) region proposed for 5G applications. The design consists of two monopole elements with full size of 26 × 11 mm². The two monopoles are designed to provide dual-band operation at the frequencies 27 GHz and 39 GHz. The mutual coupling between the two elements is studied and optimized to maximally reduce the effect of one element on the other. The S-parameters of the proposed MMW MIMO configuration are simulated using two software and measured using VNA. The results are well agreed with considerable shifting between the measured and the simulated, which can be due to the fabrication tolerance and cable losses. The radiation characteristics are investigated in terms of gain and efficiency. The proposed MIMO manifests acceptable gain that reaches 5 dBi and 5.7 dBi in the first and second bands, respectively, while the radiation efficiency reaches 99.5% and 98.6% over the first and the second bands, respectively. The MIMO performance is also studied where a very low envelope correlation of about 10^–4 is obtained and a diversity gain of about 10 dB over the two operating bands is also achieved. The comparison between simulation and measurement shows the possible potential of the proposed MIMO antenna that makes it feasible for MMW 5G applications.