A wideband perforated rectangular dielectric resonator antenna (RDRA) reflectarray is presented. The arrays of RDRA are formed from
one piece of materials. Air-filled holes are drilled into the material around the RDRA. This
technique of fabricating RDRA reflectarray using
perforations eliminates the need to position and
bond individual elements in the reflectarray and
makes the fabrication of the RDRA reflectarray
feasible. The ground plane below the reflectarray
elements is folded as a rectangular concave
surface so that an air-gap is formed between the
RDRA elements and the ground plane in order to
increase the bandwidth. Full-wave analysis using
the finite integration technique is applied. Three cases are studied. In the first one, the horn antenna is placed at the focal point to illuminate the reflectarray and the main beam in the broadside direction. In the second one, the horn antenna is placed at the focal point and the main beam at ±30 degrees off broadside direction. In the third one, an offset feed RDRA reflectarray is considered. A variable length RDRA provides the required phase shift at each cell on the reflectarray surface. The normalized gain patterns, the frequency bandwidth, and the aperture efficiency for the above cases are calculated. |
