A two-beam waveguide slot array with sidelobe suppression

A low sidelobe two-beam waveguide slot array is designed and measured. The antenna structure should be symmetrical for realizing two symmetrical beams which imposes restriction in slot design for the sidelobe and the gain. Th e slot coupling distribution is optimized numerically for side-lobe suppres sion under the condition of the structural symmetry. The first side-lobe le vel is minimized for the specific antenna efficiency in the continuous sour ce model. This synthesis is reinforced by the full wave slot analysis using the method of moments. The design is confirmed by experiments using a one- dimensional array at 12 GHz and the good agreements between the predictions : and the measurements are observed.