Reduction of Long Line Effects in Single-Layer Slotted Waveguide Arrays With an Embedded Partially Corporate Feed

Single-layer slotted waveguide arrays have various advantages such as low cost and mass productivity for fabrication, high gain and efficiency especially in millimeter wave band. They have traveling wave operation and the bandwidth becomes inherently narrower due to the long line effect as the antenna gain increases. This paper proposes the partially corporate feed in the single-layer structure, which inherits the advantage of low cost in fabrication. The bandwidth enhancement as well as the degradation due to the non radiating area in the aperture is assessed. The feasibility/potential of the embedded partially corporate feed is demonstrated by the experiments using the E- to H-plane power divider with very small blockage.