Design and measurement of a circularly polarized Ka-band reflectarray antenna

Reflectarray antennas are composed of phased elements to mimic conventional curved reflectors. An important step of the reflectarray antenna design is the selection of array elements, whose performance strongly determines the system behavior. This paper compares the bandwidth, fabrication tolerance, and design flexibility characteristics of several types of elements for Ka-band operation. Based on this investigation, a Ka-band circularly polarized reflectarray antenna is designed and a prototype is fabricated and measured in a planar near field measurement system. This designed antenna provides a possible choice for the sub-array of a recently developed single-layer multi-band reflectarray antenna.