Multi-faceted antenna arrays for millimeter waves and 5G -

Abstract

Fifth generation networks are the solution of the increasing number of devices and many requirements need to be met when designing such systems. Antennas, used in these systems, are restricted in size and have to have high directive steerable beams and high gain as well as many other requirements. Therefore, the choice of the operating frequency and the used substrate for the antennas create an important challenge in the antenna design process as well as the shape and the size of the antenna to achieve an optimal gain. In this thesis, planar microstrip antenna arrays having triangular shaped patches as well as multiple three-dimensional antenna designs made of planar antenna arrays of the same size are designed for fifth generation mobile communication systems. All of the proposed antennas are designed on an aluminum oxide ceramic substrate and the 3D antennas are composed of different configurations of planar antenna arrays. The frequency tunability of these antennas is tested on a nine-element antenna array by adding varactors to each patch of it. The capability of beam steering the radiation patterns of these antennas is tested on a MIMO nine-element antenna array by creating different phase shifts on its input points. Also, for the 3D antennas, beam steering was proven to be feasible through a mechanical rotating process of all the planar arrays forming the 3D antenna around one fixed axis. The simulated results show good matching in all the designs since the reflection coefficients are less -10 dB at around 30 GHz. Gain and radiation patterns of the antennas were also investigated. Obtained simulation results show that these antennas are suitable for millimeter wave communications. The next step will be to fabricate and measure these antennas.