An antenna includes a plurality of upper electrodes in a first metal layer, a plurality of lower electrodes in a second metal layer, a plurality of side electrodes connecting the upper electrodes with the lower electrodes, and a ground structure. The upper electrodes, the lower electrodes and the side electrodes form one continuous electrode. The continuous electrode extends in a first direction away from a reference plane over a substrate. The upper electrodes extend in a second direction different from the first direction. The upper electrodes, the lower electrodes, and the side electrodes are embedded within a waveguide structure that includes a dielectric material. The substrate has a length extending in the first direction greater than a length the continuous electrode extends in the first direction. The waveguide structure includes a portion of the substrate in a region beyond the length of the continuous electrode in the first direction.