This paper presents a novel concept named meta-waveguide structures to design slot array antennas based on metasurface. The proposed method investigates the geometrical parameters of the embedded metasurface and their relations to build up the engineered electric and magnetic fields to introduce efficient slot array antennas. This approach eliminates the necessity of using the well-known offsets in typical slot arrays, which can be benefited from linear array theorem. This idea is realized by employing successive filed curvature along the propagation direction, utilizing periodic metasurfaces. Thereafter, a step-by-step algorithm is recommended to design an efficient slot array antenna. Finally, a prototype is fabricated and tested experimentally validating the theoretical calculations.
