Double-ridged slot array on the board wall of a single-ridged waveguide

A novel double-ridged slot array antenna on the broad side of a single-ridged rectangular waveguide has been developed. The design is based on using a single-ridged waveguide as a series feed for an array of transverse slot radiators located along its broad wall. The main lobe radiation direction is 60 degrees and the gain is 10 dB. The waveguide broadwall dimension that is needed for the main lobe direction is 25% smaller than that for the rectangular waveguide. The main lobe scanning as a function of frequency is +or-2 degrees and the antenna standing wave ratio is better than 1.62:1 over the 5% bandwidth.<>