Frequency response of a new genetically optimized microstrip reflectarray

In future, it is conceivable that satellite antennas will need to target a single house. Meeting this requirement, antennas that are larger and lighter must be designed. Example of antennas able to radiate narrow beams are reflector antennas and antenna arrays. Printed reflectarrays combine advantages of both reflectors and printed arrays. They consist in arrays of printed patches, generally of rectangular shape, that re-radiate the illuminating power from a primary feed horn back into space. As the elements have different positions, and the field that propagates from the feed to the patches covers different path lengths, it becomes necessary to adjust the phase of single elements to compensate the different path lengths. We analyze a configuration obtained by varying the length of a stub, the position of the elements and their relative orientation. Moreover, in order to compensate the frequency shift of individual elements introduced by the presence of the stubs, the dimensions of the patches are varied, too. Since the bandwidth of this kind of radiator is it particularly critical issue, a frequency response analysis of the genetically optimized configuration has also been performed.