Ridged waveguide slot antenna array with low cross-polarization

A novel low cross-polarized waveguide slot antenna array with V-shaped slots in ridged waveguide is presented. The V-shaped slot consists of a pair of tilted slots connected end-to-end which cut in the dual narrow walls symmetrically. Since the co-polar fields from the tilted slots will add in phase toward boresight while the cross polarized fields cancel, the cross-polarization will be improved in H-plane significantly. A 16-element linear array is designed, fabricated and tested. The measured cross-polarization level is less than -40 dB over the entire bandwidth, verified the design.