A mm-Wave 5G Double Slot Array Antenna Based on Gap Waveguide Technology and Glide Symmetries

We propose a double slot array antenna based on Gap Waveguide Technology for 5G mm-Waves wireless systems. The antenna is formed by assembling three metal layers, the so-called feed, cavity, and radiation layers. A double slot array at the radiation layer is backed by the cavity layer which is fed by a ridge gap waveguide corporate feeding network. The double slot configuration provides better control of the impedance bandwidth at the cost of increasing sidelobes. In addition, a glide-symmetry metasurface is integrated into the intermediate and upper layers. This eliminates energy leakages that may occur if any gap exists between the two layers. The realization of metasurface via holey glide symmetry allows for larger periodicity and much-reduced milling depth in comparison with using periodic metal pins. Hence, the fabrication cost of the cavity layer is considerably lower. A prototype of a $4\times 4$ double slot configuration is designed, fabricated, and measured. The measurement results show an 11.4% achieved impedance bandwidth (S $_{11} \lt $ -10 dB), covering the 37.20 GHz - 41.58 GHz frequency range. The measured normalized radiation patterns show that the level of lateral lobes is below -9 dB and -10 dB at $\varphi = 0^{\mathrm {o}}$ and $\varphi = 90^{\mathrm {o}}$ respectively over the operating frequency range, while the measured peak gain ranges from 16.56 dBi to 18.75 dBi, and the aperture efficiency is up to 75%. Measurements are in good agreement with the simulations.