An Accurate and Efficient Design Tool for Large Contoured Beam Reflectarrays

An accurate and efficient tool for the design of contoured beam reflectarrays is presented. It is based on the Spectral Domain Method of Moments, the Local Periodicity approach, and a minimax optimization algorithm. Contrary to the conventional phase-only optimization techniques, the geometrical parameters of the array elements are directly optimized to fulfill the far-field requirements. The design tool can be used to optimize reflectarrays based on a regular grid as well as an irregular grid. Both coand cross-polar radiation can be optimized for multiple frequencies, polarizations, and feed illuminations. Two offset contoured beam reflectarrays that radiate a highgain beam on an European coverage have been designed, manufactured, and measured at the DTU-ESA Spherical Near-Field Antenna Test Facility. An excellent agreement is obtained for the simulated and measured patterns. To show the design tool’s ability to optimize electrically large reflectarrays, a 50 × 50 square wavelengths contoured beam reflectarray has been designed.