Improving Co- to Cross-Polarization Ratio of Vivaldi Antenna Using TE20 Mode SIW Launcher

To reduce the cross-polarization of antipodal Vivaldi antenna (AVA), the TE₂₀ mode of the substrate integrated waveguide (SIW) is used, which can feed two AVAs that are mirrored copy relative to each other with the same amplitude and opposite phase on the X band. The proposed structure is planar, and since it has been implemented in SIW technology, this lightweight and low profile antenna has low leakage of power in the undesired direction and is relatively low-cost.