The design, manufacture and characterization of a slotted waveguide antenna using substrate-integrated waveguide (SIW) technology combined with a metasurface are described in this paper. The inclusion of the metasurface serves to augment the radiating aperture and narrows the E-plane cut of the antenna pattern, a characteristic that would otherwise be dictated by the slots. For demonstration, an 8-element slotted SIW (S-SIW) antenna array with a −20 dB sidelobe level Chebyshev distribution was designed and its performance was compared to that of a conventional slotted SIW array. Owing to the metasurface, the radiation pattern E-plane narrows and 3 dB gain improvement has been achieved, while keeping matching unaffected.
