3D bifocal design method for dual reflectarray configurations with application to multi-beam satellite antennas in Ka-Band

This contribution describes a 3D bifocal design technique for dual reflectarray configurations with application to multi-beam satellite antennas in Ka-band. The bifocal technique has been used to obtain closer beams than those obtained with a single-focus antenna and, at the same time, to improve the performance of the extreme beams. A bifocal dual reflectarray antenna demonstrator in an offset compact-range configuration has been designed, fabricated and tested. The demonstrator generates 10 beams alternating in dual-linear polarization when the antenna is illuminated by 5 adjacent feed-horns. The results are in good agreement with the design requirements in the 19.2-20.2 GHz band