A Symmetrical Dual-Beam Bowtie Antenna With Gain Enhancement Using Metamaterial for 5G MIMO Applications

A symmetrical dual-beam end-fire bowtie antenna with gain enhancement is achieved by integrating three pairs of metamaterial (MTM) arrays for 5G MIMO applications. The first pair of MTM array with high refractive index (HRI) are deployed to form a wide beam antenna. The second pair of HRI MTM array are arranged along the end-fire direction (x-direction) in front of the radiators in order to split the single wide beam into dual beam. Besides, the third pair of anisotropic MTM array with HRI along x-direction and near zero refractive along y-direction are incorporated in front of the second pair of MTM array to improve the gain performance. The proposed technique is verified by both the full-wave electromagnetic simulation and experiment, and the simulated and measured results agree very well with each other. Moreover, the measured results reveal that the main beam directions of the proposed antenna point to ± 30° with respect to the end-fire direction (0°) over 24.25-27.5 GHz, with a maximum gain of 7.4 dBi at 26 GHz and a 4.2 dB gain improvement compared to the wide beam antenna.