Broadband reflectarray antenna with double cross loop elements

A reflectarray antenna composed of double cross loop elements of varying arm length printed on a conductor-backed substrate is introduced. Two different realizations are presented: in the first design, the lengths of both constituent arms of the cell elements are varied whereas the length of only one of the two arms is varied in the second design. Prototype reflectarrays were fabricated and measured. Measured results demonstrate a radiation efficiency of close to 55% and a 1-dB gain bandwidth of 10%, for both antennas.