Radial Line Slot Antenna Based on Different Periodic Nail Structures with Wide Gain Bandwidth

This article proposes a wide gain bandwidth RLSA. By using non-uniform periodic metal nails instead of dielectric materials, different dielectric constant regions are set within the radial waveguide.Based on this radial waveguide, the slot antenna achieved a larger gain bandwidth. The simulation results show that at the frequency of 30 GHz, the 3 dB gain bandwidth reaches $9.60 \%$. Throughout the entire gain bandwidth, the antenna achieves the performance with reflection coefficients below $\mathbf{- 1 0 d B}$ and axial ratios below −3 dB.